172972931 has 2 divisors, whose sum is σ = 172972932. Its totient is φ = 172972930.

The previous prime is 172972879. The next prime is 172972939. The reversal of 172972931 is 139279271.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 172972931 - 2¹⁸ = 172710787 is a prime.

It is a super-2 number, since 2×172972931² = 59839269717461522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (172972939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86486465 + 86486466.

It is an arithmetic number, because the mean of its divisors is an integer number (86486466).

Almost surely, 2^172972931 is an apocalyptic number.

172972931 is a deficient number, since it is larger than the sum of its proper divisors (1).

172972931 is an equidigital number, since it uses as much as digits as its factorization.

172972931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47628, while the sum is 41.

The square root of 172972931 is about 13151.9173887308. The cubic root of 172972931 is about 557.1764023915.

The spelling of 172972931 in words is "one hundred seventy-two million, nine hundred seventy-two thousand, nine hundred thirty-one".