172106998721 has 12 divisors (see below), whose sum is σ = 200624094720. Its totient is φ = 147212289000.

The previous prime is 172106998709. The next prime is 172106998769. The reversal of 172106998721 is 127899601271.

It is a de Polignac number, because none of the positive numbers 2^k-172106998721 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (172106998781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3642905 + ... + 3689846.

It is an arithmetic number, because the mean of its divisors is an integer number (16718674560).

Almost surely, 2^172106998721 is an apocalyptic number.

It is an amenable number.

172106998721 is a deficient number, since it is larger than the sum of its proper divisors (28517095999).

172106998721 is an equidigital number, since it uses as much as digits as its factorization.

172106998721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7333244 (or 7333237 counting only the distinct ones).

The product of its (nonzero) digits is 762048, while the sum is 53.

The spelling of 172106998721 in words is "one hundred seventy-two billion, one hundred six million, nine hundred ninety-eight thousand, seven hundred twenty-one".