172805117 has 2 divisors, whose sum is σ = 172805118. Its totient is φ = 172805116.

The previous prime is 172805111. The next prime is 172805161. The reversal of 172805117 is 711508271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 157602916 + 15202201 = 12554^2 + 3899^2 .

It is an emirp because it is prime and its reverse (711508271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 172805117 - 2⁸ = 172804861 is a prime.

It is a super-2 number, since 2×172805117² = 59723216922767378, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (172805111) 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, 86402558 + 86402559.

It is an arithmetic number, because the mean of its divisors is an integer number (86402559).

Almost surely, 2^172805117 is an apocalyptic number.

It is an amenable number.

172805117 is a deficient number, since it is larger than the sum of its proper divisors (1).

172805117 is an equidigital number, since it uses as much as digits as its factorization.

172805117 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3920, while the sum is 32.

The square root of 172805117 is about 13145.5360103725. The cubic root of 172805117 is about 556.9961578983.

The spelling of 172805117 in words is "one hundred seventy-two million, eight hundred five thousand, one hundred seventeen".