664801584172 has 12 divisors (see below), whose sum is σ = 1269166660776. Its totient is φ = 302182538240.

The previous prime is 664801584133. The next prime is 664801584173. The reversal of 664801584172 is 271485108466.

It is a super-2 number, since 2×664801584172² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (664801584173) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7554563413 + ... + 7554563500.

It is an arithmetic number, because the mean of its divisors is an integer number (105763888398).

Almost surely, 2^664801584172 is an apocalyptic number.

It is an amenable number.

664801584172 is a deficient number, since it is larger than the sum of its proper divisors (604365076604).

664801584172 is a wasteful number, since it uses less digits than its factorization.

664801584172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15109126928 (or 15109126926 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 52.

The spelling of 664801584172 in words is "six hundred sixty-four billion, eight hundred one million, five hundred eighty-four thousand, one hundred seventy-two".