664522320 has 360 divisors, whose sum is σ = 2639643552. Its totient is φ = 137786880.

The previous prime is 664522307. The next prime is 664522343. The reversal of 664522320 is 23225466.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1422727 + ... + 1423193.

Almost surely, 2^664522320 is an apocalyptic number.

664522320 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664522320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1319821776).

664522320 is an abundant number, since it is smaller than the sum of its proper divisors (1975121232).

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

664522320 is a wasteful number, since it uses less digits than its factorization.

664522320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519 (or 495 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 664522320 is about 25778.3304346887. The cubic root of 664522320 is about 872.6428290298.

Adding to 664522320 its reverse (23225466), we get a palindrome (687747786).

The spelling of 664522320 in words is "six hundred sixty-four million, five hundred twenty-two thousand, three hundred twenty".