645916538272 has 48 divisors (see below), whose sum is σ = 1295094370752. Its totient is φ = 317042736640.

The previous prime is 645916538257. The next prime is 645916538297. The reversal of 645916538272 is 272835619546.

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, 80698 + ... + 1139449.

It is an arithmetic number, because the mean of its divisors is an integer number (26981132724).

Almost surely, 2^645916538272 is an apocalyptic number.

It is an amenable number.

645916538272 is an abundant number, since it is smaller than the sum of its proper divisors (649177832480).

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

645916538272 is a wasteful number, since it uses less digits than its factorization.

645916538272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1220461 (or 1220453 counting only the distinct ones).

The product of its digits is 21772800, while the sum is 58.

The spelling of 645916538272 in words is "six hundred forty-five billion, nine hundred sixteen million, five hundred thirty-eight thousand, two hundred seventy-two".