172807913 has 2 divisors, whose sum is σ = 172807914. Its totient is φ = 172807912.

The previous prime is 172807891. The next prime is 172807933. The reversal of 172807913 is 319708271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 97673689 + 75134224 = 9883^2 + 8668^2 .

It is an emirp because it is prime and its reverse (319708271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 172807913 - 2²² = 168613609 is a prime.

It is not a weakly prime, because it can be changed into another prime (172807933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86403956 + 86403957.

It is an arithmetic number, because the mean of its divisors is an integer number (86403957).

Almost surely, 2^172807913 is an apocalyptic number.

It is an amenable number.

172807913 is a deficient number, since it is larger than the sum of its proper divisors (1).

172807913 is an equidigital number, since it uses as much as digits as its factorization.

172807913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 172807913 is about 13145.6423578310. The cubic root of 172807913 is about 556.9991619622. Note that the first 3 decimals are identical.

The spelling of 172807913 in words is "one hundred seventy-two million, eight hundred seven thousand, nine hundred thirteen".