66015662172 has 12 divisors (see below), whose sum is σ = 154036545096. Its totient is φ = 22005220720.

The previous prime is 66015662161. The next prime is 66015662191. The reversal of 66015662172 is 27126651066.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-3 number, since 3×66015662172³ (a number of 33 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2750652579 + ... + 2750652602.

It is an arithmetic number, because the mean of its divisors is an integer number (12836378758).

Almost surely, 2^66015662172 is an apocalyptic number.

It is an amenable number.

66015662172 is an abundant number, since it is smaller than the sum of its proper divisors (88020882924).

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

66015662172 is a wasteful number, since it uses less digits than its factorization.

66015662172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5501305188 (or 5501305186 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 42.

The spelling of 66015662172 in words is "sixty-six billion, fifteen million, six hundred sixty-two thousand, one hundred seventy-two".