640408046 has 16 divisors (see below), whose sum is σ = 967625568. Its totient is φ = 317872800.

The previous prime is 640408039. The next prime is 640408061. The reversal of 640408046 is 640804046.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 267776 + ... + 270156.

It is an arithmetic number, because the mean of its divisors is an integer number (60476598).

Almost surely, 2^640408046 is an apocalyptic number.

640408046 is a deficient number, since it is larger than the sum of its proper divisors (327217522).

640408046 is a wasteful number, since it uses less digits than its factorization.

640408046 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3307.

The product of its (nonzero) digits is 18432, while the sum is 32.

The square root of 640408046 is about 25306.2847134857. The cubic root of 640408046 is about 861.9569846986.

The spelling of 640408046 in words is "six hundred forty million, four hundred eight thousand, forty-six".