172157099 has 4 divisors (see below), whose sum is σ = 175820064. Its totient is φ = 168494136.

The previous prime is 172157087. The next prime is 172157101. The reversal of 172157099 is 990751271.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 172157099 - 2⁸ = 172156843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172157039) 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 3 ways as a sum of consecutive naturals, for example, 1831412 + ... + 1831505.

It is an arithmetic number, because the mean of its divisors is an integer number (43955016).

Almost surely, 2^172157099 is an apocalyptic number.

172157099 is a deficient number, since it is larger than the sum of its proper divisors (3662965).

172157099 is an equidigital number, since it uses as much as digits as its factorization.

172157099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3662964.

The product of its (nonzero) digits is 39690, while the sum is 41.

The square root of 172157099 is about 13120.8650248373. The cubic root of 172157099 is about 556.2990418571.

The spelling of 172157099 in words is "one hundred seventy-two million, one hundred fifty-seven thousand, ninety-nine".