172508161 has 16 divisors (see below), whose sum is σ = 199713024. Its totient is φ = 145957824.

The previous prime is 172508137. The next prime is 172508191. The reversal of 172508161 is 161805271.

It is a cyclic number.

It is not a de Polignac number, because 172508161 - 2¹⁵ = 172475393 is a prime.

It is a super-2 number, since 2×172508161² = 59518131223203842, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (172508191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 201811 + ... + 202663.

It is an arithmetic number, because the mean of its divisors is an integer number (12482064).

Almost surely, 2^172508161 is an apocalyptic number.

It is an amenable number.

172508161 is a deficient number, since it is larger than the sum of its proper divisors (27204863).

172508161 is a wasteful number, since it uses less digits than its factorization.

172508161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1200.

The product of its (nonzero) digits is 3360, while the sum is 31.

The square root of 172508161 is about 13134.2362168495. The cubic root of 172508161 is about 556.6769193055.

The spelling of 172508161 in words is "one hundred seventy-two million, five hundred eight thousand, one hundred sixty-one".