640818576 has 30 divisors (see below), whose sum is σ = 1793402390. Its totient is φ = 213606144.

The previous prime is 640818559. The next prime is 640818589. The reversal of 640818576 is 675818046.

It is a happy number.

640818576 is a `hidden beast` number, since 64 + 0 + 8 + 18 + 576 = 666.

It can be written as a sum of positive squares in only one way, i.e., 442008576 + 198810000 = 21024^2 + 14100^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2224921 + ... + 2225208.

Almost surely, 2^640818576 is an apocalyptic number.

It is an amenable number.

640818576 is an abundant number, since it is smaller than the sum of its proper divisors (1152583814).

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

640818576 is a wasteful number, since it uses less digits than its factorization.

640818576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4450143 (or 4450134 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The square root of 640818576 is about 25314.3946402042. The cubic root of 640818576 is about 862.1411295923.

The spelling of 640818576 in words is "six hundred forty million, eight hundred eighteen thousand, five hundred seventy-six".