| Base | Representation |
|---|---|
| bin | 100110100000010… |
| … | …000001001110100 |
| 3 | 1200000112122021210 |
| 4 | 212200100021310 |
| 5 | 2310333121410 |
| 6 | 144033441420 |
| 7 | 22002546540 |
| oct | 4640201164 |
| 9 | 1600478253 |
| 10 | 645988980 |
| 11 | 30170a09a |
| 12 | 160410270 |
| 13 | a3aab400 |
| 14 | 61b18a20 |
| 15 | 3baa4220 |
| hex | 26810274 |
645988980 has 288 divisors, whose sum is σ = 2361139200. Its totient is φ = 128853504.
The previous prime is 645988969. The next prime is 645988991. The reversal of 645988980 is 89889546.
645988980 = T2680 + T2681 + ... + T2848.
It is an interprime number because it is at equal distance from previous prime (645988969) and next prime (645988991).
It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.
It is a Harshad number since it is a multiple of its sum of digits (57).
It is a self number, because there is not a number n which added to its sum of digits gives 645988980.
It is a congruent number.
It is an unprimeable number.
It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1348381 + ... + 1348859.
It is an arithmetic number, because the mean of its divisors is an integer number (8198400).
Almost surely, 2645988980 is an apocalyptic number.
645988980 is a gapful number since it is divisible by the number (60) formed by its first and last digit.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 645988980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1180569600).
645988980 is an abundant number, since it is smaller than the sum of its proper divisors (1715150220).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
645988980 is a wasteful number, since it uses less digits than its factorization.
645988980 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 543 (or 528 counting only the distinct ones).
The product of its (nonzero) digits is 4976640, while the sum is 57.
The square root of 645988980 is about 25416.3132653027. The cubic root of 645988980 is about 864.4536315982.
The spelling of 645988980 in words is "six hundred forty-five million, nine hundred eighty-eight thousand, nine hundred eighty".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.091 sec. • engine limits •