166720172 has 6 divisors (see below), whose sum is σ = 291760308. Its totient is φ = 83360084.

The previous prime is 166720129. The next prime is 166720181. The reversal of 166720172 is 271027661.

166720172 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20840018 + ... + 20840025.

It is an arithmetic number, because the mean of its divisors is an integer number (48626718).

Almost surely, 2^166720172 is an apocalyptic number.

It is an amenable number.

166720172 is a deficient number, since it is larger than the sum of its proper divisors (125040136).

166720172 is a wasteful number, since it uses less digits than its factorization.

166720172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41680047 (or 41680045 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 32.

The square root of 166720172 is about 12912.0165737192. The cubic root of 166720172 is about 550.3800920877.

The spelling of 166720172 in words is "one hundred sixty-six million, seven hundred twenty thousand, one hundred seventy-two".