31,536,000
31,536,000 seconds is a common year of 365 days, and the number that appears in cache headers and certificate lifetimes.
- Even
- Composite
Where 31,536,000 fits
Why 31,536,000 is special
Where a duration has to be written in seconds, this is what 'a year' usually means — HTTP's max-age, HSTS policies, and token expiries all use it. It is not an astronomical figure at all: it is 365 × 86,400, chosen because it is easy to reason about rather than because it matches the Earth.
Factors & digit properties
- Divisors (256)
- 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 25, 27, 30, 32, 36, 40, 45, 48, 50, 54, 60, 64, 72, 73, 75, 80, 90, 96, 100, 108, 120, 125, 128, 135, 144, 146, 150, 160, 180, 192, 200, 216, 219, 225, 240, 250, 270, 288, 292, 300, 320, 360, 365, 375, 384, 400, 432, 438, 450, 480, 500, 540, 576, 584, 600, 640, 657, 675, 720, 730, 750, 800, 864, 876, 900, 960, 1000, 1080, 1095, 1125, 1152, 1168, 1200, 1314, 1350, 1440, 1460, 1500, 1600, 1728, 1752, 1800, 1825, 1920, 1971, 2000, 2160, 2190, 2250, 2336, 2400, 2628, 2700, 2880, 2920, 3000, 3200, 3285, 3375, 3456, 3504, 3600, 3650, 3942, 4000, 4320, 4380, 4500, 4672, 4800, 5256, 5400, 5475, 5760, 5840, 6000, 6570, 6750, 7008, 7200, 7300, 7884, 8000, 8640, 8760, 9000, 9125, 9344, 9600, 9855, 10512, 10800, 10950, 11680, 12000, 13140, 13500, 14016, 14400, 14600, 15768, 16000, 16425, 17280, 17520, 18000, 18250, 19710, 21024, 21600, 21900, 23360, 24000, 26280, 27000, 27375, 28032, 28800, 29200, 31536, 32850, 35040, 36000, 36500, 39420, 42048, 43200, 43800, 46720, 48000, 49275, 52560, 54000, 54750, 58400, 63072, 65700, 70080, 72000, 73000, 78840, 82125, 84096, 86400, 87600, 98550, 105120, 108000, 109500, 116800, 126144, 131400, 140160, 144000, 146000, 157680, 164250, 175200, 197100, 210240, 216000, 219000, 233600, 246375, 252288, 262800, 292000, 315360, 328500, 350400, 394200, 420480, 432000, 438000, 492750, 525600, 584000, 630720, 657000, 700800, 788400, 876000, 985500, 1051200, 1168000, 1261440, 1314000, 1576800, 1752000, 1971000, 2102400, 2628000, 3153600, 3504000, 3942000, 5256000, 6307200, 7884000, 10512000, 15768000, 31536000
- Prime factorisation
- 2^7 × 3^3 × 5^3 × 73
- Digit sum
- 18
- Digital root
- 9
Representations
- Decimal
- 31536000
- Scientific notation
- 3.154 × 10^7
Roman numerals
Roman numerals as modelled here goes up to 3,999.
Binary
1 1 1 1 0 0 0 0 1 0 0 1 1 0 0 1 1 1 0 0 0 0 0 0 0
1 × 16,777,216 + 1 × 8,388,608 + 1 × 4,194,304 + 1 × 2,097,152 + 0 × 1,048,576 + 0 × 524,288 + 0 × 262,144 + 0 × 131,072 + 1 × 65,536 + 0 × 32,768 + 0 × 16,384 + 1 × 8,192 + 1 × 4,096 + 0 × 2,048 + 0 × 1,024 + 1 × 512 + 1 × 256 + 1 × 128 + 0 × 64 + 0 × 32 + 0 × 16 + 0 × 8 + 0 × 4 + 0 × 2 + 0 × 1 = 31,536,000
Octal
1 7 0 2 3 1 6 0 0
1 × 16,777,216 + 7 × 2,097,152 + 0 × 262,144 + 2 × 32,768 + 3 × 4,096 + 1 × 512 + 6 × 64 + 0 × 8 + 0 × 1 = 31,536,000
Hexadecimal
1 e 1 3 3 8 0
1 × 16,777,216 + e × 1,048,576 + 1 × 65,536 + 3 × 4,096 + 3 × 256 + 8 × 16 + 0 × 1 = 31,536,000
Other mathematical patterns
- Abundant number
- Harshad (Niven) number
Technology & computing
Seconds in a common year of 365 days is 31,536,000. The figure that appears in HSTS policies and cache headers when the intent is 'a year', chosen over the calendar year's 31,556,952 because it needs no explanation and errs short.
DocumentedTechnology & computingGeography: worldwide
Common questions
Is 31,536,000 a prime number?
No, 31,536,000 is not prime.
What are the factors of 31,536,000?
The factors of 31,536,000 are 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20, 24, 25, 27, 30, 32, 36, 40, 45, 48, 50, 54, 60, 64, 72, 73, 75, 80, 90, 96, 100, 108, 120, 125, 128, 135, 144, 146, 150, 160, 180, 192, 200, 216, 219, 225, 240, 250, 270, 288, 292, 300, 320, 360, 365, 375, 384, 400, 432, 438, 450, 480, 500, 540, 576, 584, 600, 640, 657, 675, 720, 730, 750, 800, 864, 876, 900, 960, 1000, 1080, 1095, 1125, 1152, 1168, 1200, 1314, 1350, 1440, 1460, 1500, 1600, 1728, 1752, 1800, 1825, 1920, 1971, 2000, 2160, 2190, 2250, 2336, 2400, 2628, 2700, 2880, 2920, 3000, 3200, 3285, 3375, 3456, 3504, 3600, 3650, 3942, 4000, 4320, 4380, 4500, 4672, 4800, 5256, 5400, 5475, 5760, 5840, 6000, 6570, 6750, 7008, 7200, 7300, 7884, 8000, 8640, 8760, 9000, 9125, 9344, 9600, 9855, 10512, 10800, 10950, 11680, 12000, 13140, 13500, 14016, 14400, 14600, 15768, 16000, 16425, 17280, 17520, 18000, 18250, 19710, 21024, 21600, 21900, 23360, 24000, 26280, 27000, 27375, 28032, 28800, 29200, 31536, 32850, 35040, 36000, 36500, 39420, 42048, 43200, 43800, 46720, 48000, 49275, 52560, 54000, 54750, 58400, 63072, 65700, 70080, 72000, 73000, 78840, 82125, 84096, 86400, 87600, 98550, 105120, 108000, 109500, 116800, 126144, 131400, 140160, 144000, 146000, 157680, 164250, 175200, 197100, 210240, 216000, 219000, 233600, 246375, 252288, 262800, 292000, 315360, 328500, 350400, 394200, 420480, 432000, 438000, 492750, 525600, 584000, 630720, 657000, 700800, 788400, 876000, 985500, 1051200, 1168000, 1261440, 1314000, 1576800, 1752000, 1971000, 2102400, 2628000, 3153600, 3504000, 3942000, 5256000, 6307200, 7884000, 10512000, 15768000, 31536000.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 15 July 2026