645903156 has 24 divisors (see below), whose sum is σ = 1535544864. Its totient is φ = 211238560.

The previous prime is 645903143. The next prime is 645903161. The reversal of 645903156 is 651309546.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 507150 + ... + 508421.

It is an arithmetic number, because the mean of its divisors is an integer number (63981036).

Almost surely, 2^645903156 is an apocalyptic number.

It is an amenable number.

645903156 is an abundant number, since it is smaller than the sum of its proper divisors (889641708).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645903156 is a wasteful number, since it uses less digits than its factorization.

645903156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1015631 (or 1015629 counting only the distinct ones).

The product of its (nonzero) digits is 97200, while the sum is 39.

The square root of 645903156 is about 25414.6248447621. The cubic root of 645903156 is about 864.4153470678.

The spelling of 645903156 in words is "six hundred forty-five million, nine hundred three thousand, one hundred fifty-six".