640812470 has 16 divisors (see below), whose sum is σ = 1190671488. Its totient is φ = 248056320.

The previous prime is 640812463. The next prime is 640812479. The reversal of 640812470 is 74218046.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640812479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1033259 + ... + 1033878.

It is an arithmetic number, because the mean of its divisors is an integer number (74416968).

Almost surely, 2^640812470 is an apocalyptic number.

640812470 is a deficient number, since it is larger than the sum of its proper divisors (549859018).

640812470 is a wasteful number, since it uses less digits than its factorization.

640812470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2067175.

The product of its (nonzero) digits is 10752, while the sum is 32.

The square root of 640812470 is about 25314.2740365984. The cubic root of 640812470 is about 862.1383912975.

The spelling of 640812470 in words is "six hundred forty million, eight hundred twelve thousand, four hundred seventy".