640862508 has 48 divisors (see below), whose sum is σ = 1756774656. Its totient is φ = 179261760.

The previous prime is 640862489. The next prime is 640862587. The reversal of 640862508 is 805268046.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 185016 + ... + 188447.

It is an arithmetic number, because the mean of its divisors is an integer number (36599472).

Almost surely, 2^640862508 is an apocalyptic number.

It is an amenable number.

640862508 is an abundant number, since it is smaller than the sum of its proper divisors (1115912148).

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

640862508 is a wasteful number, since it uses less digits than its factorization.

640862508 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 373494 (or 373492 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 39.

The square root of 640862508 is about 25315.2623529759. The cubic root of 640862508 is about 862.1608308099.

The spelling of 640862508 in words is "six hundred forty million, eight hundred sixty-two thousand, five hundred eight".