664262620 has 72 divisors (see below), whose sum is σ = 1629222336. Its totient is φ = 226832256.

The previous prime is 664262593. The next prime is 664262623. The reversal of 664262620 is 26262466.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664262623) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 270237 + ... + 272683.

It is an arithmetic number, because the mean of its divisors is an integer number (22628088).

Almost surely, 2^664262620 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664262620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (814611168).

664262620 is an abundant number, since it is smaller than the sum of its proper divisors (964959716).

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

664262620 is a wasteful number, since it uses less digits than its factorization.

664262620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2747 (or 2738 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 34.

The square root of 664262620 is about 25773.2927659622. The cubic root of 664262620 is about 872.5291358978.

The spelling of 664262620 in words is "six hundred sixty-four million, two hundred sixty-two thousand, six hundred twenty".