172231157 has 4 divisors (see below), whose sum is σ = 196835616. Its totient is φ = 147626700.

The previous prime is 172231123. The next prime is 172231183. The reversal of 172231157 is 751132271.

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, and also an emirpimes, since its reverse is a distinct semiprime: 751132271 = 53 ⋅14172307.

It is a cyclic number.

It is not a de Polignac number, because 172231157 - 2⁸ = 172230901 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 (172231187) 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, 12302219 + ... + 12302232.

It is an arithmetic number, because the mean of its divisors is an integer number (49208904).

Almost surely, 2^172231157 is an apocalyptic number.

It is an amenable number.

172231157 is a deficient number, since it is larger than the sum of its proper divisors (24604459).

172231157 is an equidigital number, since it uses as much as digits as its factorization.

172231157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24604458.

The product of its digits is 2940, while the sum is 29.

The square root of 172231157 is about 13123.6868676451. The cubic root of 172231157 is about 556.3787994130.

The spelling of 172231157 in words is "one hundred seventy-two million, two hundred thirty-one thousand, one hundred fifty-seven".