172315691 has 2 divisors, whose sum is σ = 172315692. Its totient is φ = 172315690.

The previous prime is 172315687. The next prime is 172315711. The reversal of 172315691 is 196513271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 172315691 - 2² = 172315687 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (172315631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86157845 + 86157846.

It is an arithmetic number, because the mean of its divisors is an integer number (86157846).

Almost surely, 2^172315691 is an apocalyptic number.

172315691 is a deficient number, since it is larger than the sum of its proper divisors (1).

172315691 is an equidigital number, since it uses as much as digits as its factorization.

172315691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11340, while the sum is 35.

The square root of 172315691 is about 13126.9071376315. The cubic root of 172315691 is about 556.4698112707.

It can be divided in two parts, 17231 and 5691, that added together give a palindrome (22922).

The spelling of 172315691 in words is "one hundred seventy-two million, three hundred fifteen thousand, six hundred ninety-one".