664818171612 has 36 divisors (see below), whose sum is σ = 1804506467400. Its totient is φ = 189948048864.

The previous prime is 664818171571. The next prime is 664818171623. The reversal of 664818171612 is 216171818466.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 565320987 + ... + 565322162.

It is an arithmetic number, because the mean of its divisors is an integer number (50125179650).

Almost surely, 2^664818171612 is an apocalyptic number.

It is an amenable number.

664818171612 is an abundant number, since it is smaller than the sum of its proper divisors (1139688295788).

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

664818171612 is a wasteful number, since it uses less digits than its factorization.

664818171612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1130643170 (or 1130643161 counting only the distinct ones).

The product of its digits is 774144, while the sum is 51.

The spelling of 664818171612 in words is "six hundred sixty-four billion, eight hundred eighteen million, one hundred seventy-one thousand, six hundred twelve".