172138845 has 16 divisors (see below), whose sum is σ = 278151552. Its totient is φ = 90897600.

The previous prime is 172138843. The next prime is 172138871. The reversal of 172138845 is 548831271.

It is not a de Polignac number, because 172138845 - 2¹ = 172138843 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172138843) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55297 + ... + 58326.

It is an arithmetic number, because the mean of its divisors is an integer number (17384472).

Almost surely, 2^172138845 is an apocalyptic number.

172138845 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

172138845 is a deficient number, since it is larger than the sum of its proper divisors (106012707).

172138845 is a wasteful number, since it uses less digits than its factorization.

172138845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113732.

The product of its digits is 53760, while the sum is 39.

The square root of 172138845 is about 13120.1693967723. The cubic root of 172138845 is about 556.2793795028.

The spelling of 172138845 in words is "one hundred seventy-two million, one hundred thirty-eight thousand, eight hundred forty-five".