664614720 has 784 divisors, whose sum is σ = 3038295168. Its totient is φ = 134369280.

The previous prime is 664614697. The next prime is 664614761. The reversal of 664614720 is 27416466.

664614720 is a `hidden beast` number, since 6 + 646 + 1 + 4 + 7 + 2 + 0 = 666.

664614720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 111 ways as a sum of consecutive naturals, for example, 17962542 + ... + 17962578.

Almost surely, 2^664614720 is an apocalyptic number.

664614720 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 664614720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1519147584).

664614720 is an abundant number, since it is smaller than the sum of its proper divisors (2373680448).

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

664614720 is a wasteful number, since it uses less digits than its factorization.

664614720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 664614720 is about 25780.1225753486. The cubic root of 664614720 is about 872.6832733499.

The spelling of 664614720 in words is "six hundred sixty-four million, six hundred fourteen thousand, seven hundred twenty".