666725542765664 has 48 divisors (see below), whose sum is σ = 1369890336054240. Its totient is φ = 318821206978560.

The previous prime is 666725542765657. The next prime is 666725542765703. The reversal of 666725542765664 is 466567245527666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62574257 + ... + 72449904.

It is an arithmetic number, because the mean of its divisors is an integer number (28539382001130).

Almost surely, 2^{666725542765664} is an apocalyptic number.

It is an amenable number.

666725542765664 is an abundant number, since it is smaller than the sum of its proper divisors (703164793288576).

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

666725542765664 is a wasteful number, since it uses less digits than its factorization.

666725542765664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135030903 (or 135030895 counting only the distinct ones).

The product of its digits is 18289152000, while the sum is 77.

The spelling of 666725542765664 in words is "six hundred sixty-six trillion, seven hundred twenty-five billion, five hundred forty-two million, seven hundred sixty-five thousand, six hundred sixty-four".