645273535256 has 16 divisors (see below), whose sum is σ = 1382729004240. Its totient is φ = 276545800800.

The previous prime is 645273535219. The next prime is 645273535259. The reversal of 645273535256 is 652535372546.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 645273535198 and 645273535207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645273535259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5761370795 + ... + 5761370906.

It is an arithmetic number, because the mean of its divisors is an integer number (86420562765).

Almost surely, 2^645273535256 is an apocalyptic number.

It is an amenable number.

645273535256 is an abundant number, since it is smaller than the sum of its proper divisors (737455468984).

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

645273535256 is a wasteful number, since it uses less digits than its factorization.

645273535256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11522741714 (or 11522741710 counting only the distinct ones).

The product of its digits is 22680000, while the sum is 53.

The spelling of 645273535256 in words is "six hundred forty-five billion, two hundred seventy-three million, five hundred thirty-five thousand, two hundred fifty-six".