664787472 has 20 divisors (see below), whose sum is σ = 1717367760. Its totient is φ = 221595808.

The previous prime is 664787471. The next prime is 664787537. The reversal of 664787472 is 274787466.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (664787471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6924822 + ... + 6924917.

It is an arithmetic number, because the mean of its divisors is an integer number (85868388).

Almost surely, 2^664787472 is an apocalyptic number.

It is an amenable number.

664787472 is an abundant number, since it is smaller than the sum of its proper divisors (1052580288).

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

664787472 is a wasteful number, since it uses less digits than its factorization.

664787472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13849750 (or 13849744 counting only the distinct ones).

The product of its digits is 3161088, while the sum is 51.

The square root of 664787472 is about 25783.4728459919. The cubic root of 664787472 is about 872.7588784166.

The spelling of 664787472 in words is "six hundred sixty-four million, seven hundred eighty-seven thousand, four hundred seventy-two".