189811915 has 12 divisors (see below), whose sum is σ = 235364832. Its totient is φ = 146947440.

The previous prime is 189811913. The next prime is 189811927. The reversal of 189811915 is 519118981.

It is a happy number.

It is not a de Polignac number, because 189811915 - 2¹ = 189811913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (189811913) 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 11 ways as a sum of consecutive naturals, for example, 14947 + ... + 24556.

It is an arithmetic number, because the mean of its divisors is an integer number (19613736).

Almost surely, 2^189811915 is an apocalyptic number.

189811915 is a deficient number, since it is larger than the sum of its proper divisors (45552917).

189811915 is an equidigital number, since it uses as much as digits as its factorization.

189811915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39570 (or 39539 counting only the distinct ones).

The product of its digits is 25920, while the sum is 43.

The square root of 189811915 is about 13777.2245027799. The cubic root of 189811915 is about 574.6999467896.

The spelling of 189811915 in words is "one hundred eighty-nine million, eight hundred eleven thousand, nine hundred fifteen".