64621620 has 72 divisors (see below), whose sum is σ = 224025984. Its totient is φ = 14770368.

The previous prime is 64621589. The next prime is 64621633. The reversal of 64621620 is 2612646.

It is a happy number.

64621620 is a `hidden beast` number, since 646 + 2 + 16 + 2 + 0 = 666.

It is a nialpdrome in base 14.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24384 + ... + 26903.

It is an arithmetic number, because the mean of its divisors is an integer number (3111472).

Almost surely, 2^64621620 is an apocalyptic number.

64621620 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64621620 is an abundant number, since it is smaller than the sum of its proper divisors (159404364).

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

64621620 is a wasteful number, since it uses less digits than its factorization.

64621620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51309 (or 51304 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 64621620 is about 8038.7573666581. The cubic root of 64621620 is about 401.2908713135.

The spelling of 64621620 in words is "sixty-four million, six hundred twenty-one thousand, six hundred twenty".