640701698 has 64 divisors (see below), whose sum is σ = 1288224000. Its totient is φ = 231807744.

The previous prime is 640701671. The next prime is 640701703. The reversal of 640701698 is 896107046.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 97088 + ... + 103476.

It is an arithmetic number, because the mean of its divisors is an integer number (20128500).

Almost surely, 2^640701698 is an apocalyptic number.

640701698 is an abundant number, since it is smaller than the sum of its proper divisors (647522302).

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

640701698 is a wasteful number, since it uses less digits than its factorization.

640701698 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6459.

The product of its (nonzero) digits is 72576, while the sum is 41.

The square root of 640701698 is about 25312.0860064910. The cubic root of 640701698 is about 862.0887115021.

The spelling of 640701698 in words is "six hundred forty million, seven hundred one thousand, six hundred ninety-eight".