172090871 has 4 divisors (see below), whose sum is σ = 172776744. Its totient is φ = 171405000.

The previous prime is 172090837. The next prime is 172090879. The reversal of 172090871 is 178090271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 178090271 = 1097 ⋅162343.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172090871 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (172090879) 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, 342560 + ... + 343061.

It is an arithmetic number, because the mean of its divisors is an integer number (43194186).

Almost surely, 2^172090871 is an apocalyptic number.

172090871 is a deficient number, since it is larger than the sum of its proper divisors (685873).

172090871 is an equidigital number, since it uses as much as digits as its factorization.

172090871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685872.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 172090871 is about 13118.3410155400. The cubic root of 172090871 is about 556.2276975277.

The spelling of 172090871 in words is "one hundred seventy-two million, ninety thousand, eight hundred seventy-one".