640474900 has 36 divisors (see below), whose sum is σ = 1496743612. Its totient is φ = 236482560.

The previous prime is 640474897. The next prime is 640474957. The reversal of 640474900 is 9474046.

640474900 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 230979204 + 409495696 = 15198^2 + 20236^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 245037 + ... + 247636.

Almost surely, 2^640474900 is an apocalyptic number.

It is an amenable number.

640474900 is an abundant number, since it is smaller than the sum of its proper divisors (856268712).

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

640474900 is a wasteful number, since it uses less digits than its factorization.

640474900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 492700 (or 492693 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 34.

The square root of 640474900 is about 25307.6055761899. The cubic root of 640474900 is about 861.9869776942.

The spelling of 640474900 in words is "six hundred forty million, four hundred seventy-four thousand, nine hundred".