664761600 has 216 divisors, whose sum is σ = 2438246720. Its totient is φ = 177223680.

The previous prime is 664761593. The next prime is 664761611. The reversal of 664761600 is 6167466.

664761600 is a `hidden beast` number, since 6 + 6 + 47 + 6 + 1 + 600 = 666.

664761600 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (216).

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 23 ways as a sum of consecutive naturals, for example, 170877 + ... + 174723.

Almost surely, 2^664761600 is an apocalyptic number.

664761600 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 664761600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1219123360).

664761600 is an abundant number, since it is smaller than the sum of its proper divisors (1773485120).

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

664761600 is a wasteful number, since it uses less digits than its factorization.

664761600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3882 (or 3857 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 664761600 is about 25782.9711243681. The cubic root of 664761600 is about 872.7475563468.

The spelling of 664761600 in words is "six hundred sixty-four million, seven hundred sixty-one thousand, six hundred".