172015889 has 4 divisors (see below), whose sum is σ = 174438720. Its totient is φ = 169593060.

The previous prime is 172015861. The next prime is 172015897. The reversal of 172015889 is 988510271.

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.

It is a cyclic number.

It is not a de Polignac number, because 172015889 - 2⁸ = 172015633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172015859) 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, 1211309 + ... + 1211450.

It is an arithmetic number, because the mean of its divisors is an integer number (43609680).

Almost surely, 2^172015889 is an apocalyptic number.

It is an amenable number.

172015889 is a deficient number, since it is larger than the sum of its proper divisors (2422831).

172015889 is an equidigital number, since it uses as much as digits as its factorization.

172015889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2422830.

The product of its (nonzero) digits is 40320, while the sum is 41.

The square root of 172015889 is about 13115.4827970609. The cubic root of 172015889 is about 556.1469008264.

The spelling of 172015889 in words is "one hundred seventy-two million, fifteen thousand, eight hundred eighty-nine".