664494500880 has 320 divisors, whose sum is σ = 2700170035200. Its totient is φ = 146984855040.

The previous prime is 664494500869. The next prime is 664494500903. The reversal of 664494500880 is 88005494466.

664494500880 is a `hidden beast` number, since 6 + 6 + 44 + 94 + 500 + 8 + 8 + 0 = 666.

664494500880 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 (54).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 240120 + ... + 1177559.

It is an arithmetic number, because the mean of its divisors is an integer number (8438031360).

Almost surely, 2^664494500880 is an apocalyptic number.

664494500880 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 664494500880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1350085017600).

664494500880 is an abundant number, since it is smaller than the sum of its proper divisors (2035675534320).

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

664494500880 is a wasteful number, since it uses less digits than its factorization.

664494500880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1417739 (or 1417727 counting only the distinct ones).

The product of its (nonzero) digits is 6635520, while the sum is 54.

The spelling of 664494500880 in words is "six hundred sixty-four billion, four hundred ninety-four million, five hundred thousand, eight hundred eighty".