640815051 has 16 divisors (see below), whose sum is σ = 908647200. Its totient is φ = 400316928.

The previous prime is 640815037. The next prime is 640815053. The reversal of 640815051 is 150518046.

640815051 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 640815051 - 2⁶ = 640814987 is a prime.

It is not an unprimeable number, because it can be changed into a prime (640815053) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15756 + ... + 39113.

It is an arithmetic number, because the mean of its divisors is an integer number (56790450).

Almost surely, 2^640815051 is an apocalyptic number.

640815051 is a deficient number, since it is larger than the sum of its proper divisors (267832149).

640815051 is a wasteful number, since it uses less digits than its factorization.

640815051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55118.

The product of its (nonzero) digits is 4800, while the sum is 30.

The square root of 640815051 is about 25314.3250156902. The cubic root of 640815051 is about 862.1395487741.

The spelling of 640815051 in words is "six hundred forty million, eight hundred fifteen thousand, fifty-one".