645475272 has 64 divisors (see below), whose sum is σ = 1797768000. Its totient is φ = 191756544.

The previous prime is 645475247. The next prime is 645475291. The reversal of 645475272 is 272574546.

645475272 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 26622 + ... + 44717.

It is an arithmetic number, because the mean of its divisors is an integer number (28090125).

Almost surely, 2^645475272 is an apocalyptic number.

It is an amenable number.

645475272 is an abundant number, since it is smaller than the sum of its proper divisors (1152292728).

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

645475272 is a wasteful number, since it uses less digits than its factorization.

645475272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71390 (or 71386 counting only the distinct ones).

The product of its digits is 470400, while the sum is 42.

The square root of 645475272 is about 25406.2053837247. The cubic root of 645475272 is about 864.2244251536.

The spelling of 645475272 in words is "six hundred forty-five million, four hundred seventy-five thousand, two hundred seventy-two".