664031440800 has 1728 divisors, whose sum is σ = 3109953450240. Its totient is φ = 129392640000.

The previous prime is 664031440753. The next prime is 664031440817. The reversal of 664031440800 is 8044130466.

664031440800 is a `hidden beast` number, since 6 + 640 + 3 + 1 + 4 + 4 + 0 + 8 + 0 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 510400150 + ... + 510401450.

It is an arithmetic number, because the mean of its divisors is an integer number (1799741580).

Almost surely, 2^664031440800 is an apocalyptic number.

664031440800 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 664031440800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1554976725120).

664031440800 is an abundant number, since it is smaller than the sum of its proper divisors (2445922009440).

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

664031440800 is a wasteful number, since it uses less digits than its factorization.

664031440800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1407 (or 1391 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The spelling of 664031440800 in words is "six hundred sixty-four billion, thirty-one million, four hundred forty thousand, eight hundred".