640404204 has 24 divisors (see below), whose sum is σ = 1630120128. Its totient is φ = 194061840.

The previous prime is 640404197. The next prime is 640404221. The reversal of 640404204 is 402404046.

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, 2425642 + ... + 2425905.

It is an arithmetic number, because the mean of its divisors is an integer number (67921672).

Almost surely, 2^640404204 is an apocalyptic number.

It is an amenable number.

640404204 is an abundant number, since it is smaller than the sum of its proper divisors (989715924).

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

640404204 is a wasteful number, since it uses less digits than its factorization.

640404204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4851565 (or 4851563 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 24.

The square root of 640404204 is about 25306.2088033747. The cubic root of 640404204 is about 861.9552609823.

The spelling of 640404204 in words is "six hundred forty million, four hundred four thousand, two hundred four".