172725521 has 8 divisors (see below), whose sum is σ = 180556800. Its totient is φ = 165035520.

The previous prime is 172725493. The next prime is 172725533. The reversal of 172725521 is 125527271.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172725521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172725571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32816 + ... + 37713.

It is an arithmetic number, because the mean of its divisors is an integer number (22569600).

Almost surely, 2^172725521 is an apocalyptic number.

It is an amenable number.

172725521 is a deficient number, since it is larger than the sum of its proper divisors (7831279).

172725521 is an equidigital number, since it uses as much as digits as its factorization.

172725521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70639.

The product of its digits is 9800, while the sum is 32.

The square root of 172725521 is about 13142.5081700564. The cubic root of 172725521 is about 556.9106251785.

The spelling of 172725521 in words is "one hundred seventy-two million, seven hundred twenty-five thousand, five hundred twenty-one".