645545212656 has 80 divisors (see below), whose sum is σ = 1788551418240. Its totient is φ = 200010021120.

The previous prime is 645545212621. The next prime is 645545212661. The reversal of 645545212656 is 656212545546.

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 645545212599 and 645545212608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6629350 + ... + 6726021.

It is an arithmetic number, because the mean of its divisors is an integer number (22356892728).

Almost surely, 2^645545212656 is an apocalyptic number.

It is an amenable number.

645545212656 is an abundant number, since it is smaller than the sum of its proper divisors (1143006205584).

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

645545212656 is a wasteful number, since it uses less digits than its factorization.

645545212656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13355454 (or 13355448 counting only the distinct ones).

The product of its digits is 8640000, while the sum is 51.

The spelling of 645545212656 in words is "six hundred forty-five billion, five hundred forty-five million, two hundred twelve thousand, six hundred fifty-six".