172605257 has 4 divisors (see below), whose sum is σ = 188296656. Its totient is φ = 156913860.

The previous prime is 172605247. The next prime is 172605269. The reversal of 172605257 is 752506271.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 172605257 - 2⁶ = 172605193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172605217) 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, 7845683 + ... + 7845704.

It is an arithmetic number, because the mean of its divisors is an integer number (47074164).

Almost surely, 2^172605257 is an apocalyptic number.

It is an amenable number.

172605257 is a deficient number, since it is larger than the sum of its proper divisors (15691399).

172605257 is a wasteful number, since it uses less digits than its factorization.

172605257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15691398.

The product of its (nonzero) digits is 29400, while the sum is 35.

The square root of 172605257 is about 13137.9319909946. The cubic root of 172605257 is about 556.7813413498.

The spelling of 172605257 in words is "one hundred seventy-two million, six hundred five thousand, two hundred fifty-seven".