664587891072 has 256 divisors, whose sum is σ = 2273244134400. Its totient is φ = 187207372800.

The previous prime is 664587891059. The next prime is 664587891109. The reversal of 664587891072 is 270198785466.

664587891072 is a `hidden beast` number, since 6 + 6 + 458 + 78 + 9 + 107 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1524172 + ... + 1911092.

It is an arithmetic number, because the mean of its divisors is an integer number (8879859900).

Almost surely, 2^664587891072 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 664587891072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1136622067200).

664587891072 is an abundant number, since it is smaller than the sum of its proper divisors (1608656243328).

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

664587891072 is a wasteful number, since it uses less digits than its factorization.

664587891072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387022 (or 387004 counting only the distinct ones).

The product of its (nonzero) digits is 40642560, while the sum is 63.

The spelling of 664587891072 in words is "six hundred sixty-four billion, five hundred eighty-seven million, eight hundred ninety-one thousand, seventy-two".