172108257 has 4 divisors (see below), whose sum is σ = 229477680. Its totient is φ = 114738836.

The previous prime is 172108253. The next prime is 172108291. The reversal of 172108257 is 752801271.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 752801271 = 3 ⋅250933757.

It is a cyclic number.

It is not a de Polignac number, because 172108257 - 2² = 172108253 is a prime.

It is not an unprimeable number, because it can be changed into a prime (172108253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28684707 + ... + 28684712.

It is an arithmetic number, because the mean of its divisors is an integer number (57369420).

Almost surely, 2^172108257 is an apocalyptic number.

It is an amenable number.

172108257 is a deficient number, since it is larger than the sum of its proper divisors (57369423).

172108257 is an equidigital number, since it uses as much as digits as its factorization.

172108257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57369422.

The product of its (nonzero) digits is 7840, while the sum is 33.

The square root of 172108257 is about 13119.0036588149. The cubic root of 172108257 is about 556.2464284247.

The spelling of 172108257 in words is "one hundred seventy-two million, one hundred eight thousand, two hundred fifty-seven".