645256564356 has 24 divisors (see below), whose sum is σ = 1505652088864. Its totient is φ = 215077887360.

The previous prime is 645256564343. The next prime is 645256564357. The reversal of 645256564356 is 653465652546.

It is a junction number, because it is equal to n+sod(n) for n = 645256564296 and 645256564305.

It is not an unprimeable number, because it can be changed into a prime (645256564357) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 596725 + ... + 1283196.

Almost surely, 2^645256564356 is an apocalyptic number.

It is an amenable number.

645256564356 is an abundant number, since it is smaller than the sum of its proper divisors (860395524508).

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

645256564356 is a wasteful number, since it uses less digits than its factorization.

645256564356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1908531 (or 1908529 counting only the distinct ones).

The product of its digits is 77760000, while the sum is 57.

The spelling of 645256564356 in words is "six hundred forty-five billion, two hundred fifty-six million, five hundred sixty-four thousand, three hundred fifty-six".