640635514 has 32 divisors (see below), whose sum is σ = 1064845440. Its totient is φ = 287519232.

The previous prime is 640635487. The next prime is 640635551. The reversal of 640635514 is 415536046.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a self number, because there is not a number n which added to its sum of digits gives 640635514.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 318837 + ... + 320839.

It is an arithmetic number, because the mean of its divisors is an integer number (33276420).

Almost surely, 2^640635514 is an apocalyptic number.

640635514 is a deficient number, since it is larger than the sum of its proper divisors (424209926).

640635514 is a wasteful number, since it uses less digits than its factorization.

640635514 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2454.

The product of its (nonzero) digits is 43200, while the sum is 34.

The square root of 640635514 is about 25310.7786130731. The cubic root of 640635514 is about 862.0590261097.

The spelling of 640635514 in words is "six hundred forty million, six hundred thirty-five thousand, five hundred fourteen".