172206317 has 4 divisors (see below), whose sum is σ = 172590300. Its totient is φ = 171822336.

The previous prime is 172206257. The next prime is 172206319. The reversal of 172206317 is 713602271.

172206317 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 713602271 = 4093 ⋅174347.

It can be written as a sum of positive squares in 2 ways, for example, as 89378116 + 82828201 = 9454^2 + 9101^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172206317 is a prime.

It is a super-2 number, since 2×172206317² = 59310031229408978, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 172206317.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172206319) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 191318 + ... + 192215.

It is an arithmetic number, because the mean of its divisors is an integer number (43147575).

Almost surely, 2^172206317 is an apocalyptic number.

It is an amenable number.

172206317 is a deficient number, since it is larger than the sum of its proper divisors (383983).

172206317 is an equidigital number, since it uses as much as digits as its factorization.

172206317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383982.

The product of its (nonzero) digits is 3528, while the sum is 29.

The square root of 172206317 is about 13122.7404531218. The cubic root of 172206317 is about 556.3520502578.

Adding to 172206317 its reverse (713602271), we get a palindrome (885808588).

The spelling of 172206317 in words is "one hundred seventy-two million, two hundred six thousand, three hundred seventeen".