641943864 has 48 divisors (see below), whose sum is σ = 1740861720. Its totient is φ = 213702720.

The previous prime is 641943857. The next prime is 641943871. The reversal of 641943864 is 468349146.

It is an interprime number because it is at equal distance from previous prime (641943857) and next prime (641943871).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 54154 + ... + 64934.

Almost surely, 2^641943864 is an apocalyptic number.

It is an amenable number.

641943864 is an abundant number, since it is smaller than the sum of its proper divisors (1098917856).

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

641943864 is a wasteful number, since it uses less digits than its factorization.

641943864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11620 (or 11613 counting only the distinct ones).

The product of its digits is 497664, while the sum is 45.

The square root of 641943864 is about 25336.6111388244. The cubic root of 641943864 is about 862.6454791781.

The spelling of 641943864 in words is "six hundred forty-one million, nine hundred forty-three thousand, eight hundred sixty-four".