645446264 has 16 divisors (see below), whose sum is σ = 1273907400. Its totient is φ = 305737632.

The previous prime is 645446261. The next prime is 645446279. The reversal of 645446264 is 462644546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645446261) 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, 2123027 + ... + 2123330.

Almost surely, 2^645446264 is an apocalyptic number.

It is an amenable number.

645446264 is a deficient number, since it is larger than the sum of its proper divisors (628461136).

645446264 is a wasteful number, since it uses less digits than its factorization.

645446264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4246382 (or 4246378 counting only the distinct ones).

The product of its digits is 552960, while the sum is 41.

The square root of 645446264 is about 25405.6344931592. The cubic root of 645446264 is about 864.2114787254.

The spelling of 645446264 in words is "six hundred forty-five million, four hundred forty-six thousand, two hundred sixty-four".