66885172 has 6 divisors (see below), whose sum is σ = 117049058. Its totient is φ = 33442584.

The previous prime is 66885151. The next prime is 66885179. The reversal of 66885172 is 27158866.

It can be written as a sum of positive squares in only one way, i.e., 63297936 + 3587236 = 7956^2 + 1894^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66885179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8360643 + ... + 8360650.

Almost surely, 2^66885172 is an apocalyptic number.

It is an amenable number.

66885172 is a deficient number, since it is larger than the sum of its proper divisors (50163886).

66885172 is a wasteful number, since it uses less digits than its factorization.

66885172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16721297 (or 16721295 counting only the distinct ones).

The product of its digits is 161280, while the sum is 43.

The square root of 66885172 is about 8178.3355274775. The cubic root of 66885172 is about 405.9226477888.

The spelling of 66885172 in words is "sixty-six million, eight hundred eighty-five thousand, one hundred seventy-two".