645658874 has 16 divisors (see below), whose sum is σ = 1165099200. Its totient is φ = 262147104.

The previous prime is 645658847. The next prime is 645658891. The reversal of 645658874 is 478856546.

It is a happy number.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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, 1213379 + ... + 1213910.

It is an arithmetic number, because the mean of its divisors is an integer number (72818700).

Almost surely, 2^645658874 is an apocalyptic number.

645658874 is a deficient number, since it is larger than the sum of its proper divisors (519440326).

645658874 is a wasteful number, since it uses less digits than its factorization.

645658874 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2427317.

The product of its digits is 6451200, while the sum is 53.

The square root of 645658874 is about 25409.8184566518. The cubic root of 645658874 is about 864.3063587290.

The spelling of 645658874 in words is "six hundred forty-five million, six hundred fifty-eight thousand, eight hundred seventy-four".