172879691 has 2 divisors, whose sum is σ = 172879692. Its totient is φ = 172879690.

The previous prime is 172879633. The next prime is 172879699. The reversal of 172879691 is 196978271.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172879691 is a prime.

It is not a weakly prime, because it can be changed into another prime (172879699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86439845 + 86439846.

It is an arithmetic number, because the mean of its divisors is an integer number (86439846).

Almost surely, 2^172879691 is an apocalyptic number.

172879691 is a deficient number, since it is larger than the sum of its proper divisors (1).

172879691 is an equidigital number, since it uses as much as digits as its factorization.

172879691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 381024, while the sum is 50.

The square root of 172879691 is about 13148.3721806161. The cubic root of 172879691 is about 557.0762702207.

The spelling of 172879691 in words is "one hundred seventy-two million, eight hundred seventy-nine thousand, six hundred ninety-one".