664533072 has 160 divisors (see below), whose sum is σ = 2207676160. Its totient is φ = 189796608.

The previous prime is 664533059. The next prime is 664533097. The reversal of 664533072 is 270335466.

664533072 is a `hidden beast` number, since 6 + 645 + 3 + 3 + 0 + 7 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 243588 + ... + 246300.

It is an arithmetic number, because the mean of its divisors is an integer number (13797976).

Almost surely, 2^664533072 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 664533072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1103838080).

664533072 is an abundant number, since it is smaller than the sum of its proper divisors (1543143088).

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

664533072 is an equidigital number, since it uses as much as digits as its factorization.

664533072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2749 (or 2725 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 36.

The square root of 664533072 is about 25778.5389810982. The cubic root of 664533072 is about 872.6475354707.

The spelling of 664533072 in words is "six hundred sixty-four million, five hundred thirty-three thousand, seventy-two".