645264646 has 24 divisors (see below), whose sum is σ = 1050061320. Its totient is φ = 297251136.

The previous prime is 645264637. The next prime is 645264647. The reversal of 645264646 is 646462546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645264647) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 215850 + ... + 218818.

It is an arithmetic number, because the mean of its divisors is an integer number (43752555).

Almost surely, 2^645264646 is an apocalyptic number.

645264646 is a deficient number, since it is larger than the sum of its proper divisors (404796674).

645264646 is a wasteful number, since it uses less digits than its factorization.

645264646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3640 (or 3627 counting only the distinct ones).

The product of its digits is 829440, while the sum is 43.

The square root of 645264646 is about 25402.0598771045. The cubic root of 645264646 is about 864.1304128061.

The spelling of 645264646 in words is "six hundred forty-five million, two hundred sixty-four thousand, six hundred forty-six".