172111631 has 2 divisors, whose sum is σ = 172111632. Its totient is φ = 172111630.

The previous prime is 172111619. The next prime is 172111729. The reversal of 172111631 is 136111271.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 172111631 - 2²⁶ = 105002767 is a prime.

It is a super-2 number, since 2×172111631² = 59244827050960322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 172111597 and 172111606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (172111831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86055815 + 86055816.

It is an arithmetic number, because the mean of its divisors is an integer number (86055816).

Almost surely, 2^172111631 is an apocalyptic number.

172111631 is a deficient number, since it is larger than the sum of its proper divisors (1).

172111631 is an equidigital number, since it uses as much as digits as its factorization.

172111631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 252, while the sum is 23.

The square root of 172111631 is about 13119.1322502672. The cubic root of 172111631 is about 556.2500632748.

The spelling of 172111631 in words is "one hundred seventy-two million, one hundred eleven thousand, six hundred thirty-one".