189515217 has 4 divisors (see below), whose sum is σ = 252686960. Its totient is φ = 126343476.

The previous prime is 189515197. The next prime is 189515219. The reversal of 189515217 is 712515981.

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: 712515981 = 3 ⋅237505327.

It is not a de Polignac number, because 189515217 - 2⁶ = 189515153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (189515219) 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, 31585867 + ... + 31585872.

It is an arithmetic number, because the mean of its divisors is an integer number (63171740).

Almost surely, 2^189515217 is an apocalyptic number.

It is an amenable number.

189515217 is a deficient number, since it is larger than the sum of its proper divisors (63171743).

189515217 is an equidigital number, since it uses as much as digits as its factorization.

189515217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63171742.

The product of its digits is 25200, while the sum is 39.

The square root of 189515217 is about 13766.4525931701. The cubic root of 189515217 is about 574.4003497814.

The spelling of 189515217 in words is "one hundred eighty-nine million, five hundred fifteen thousand, two hundred seventeen".