15399889 has 4 divisors (see below), whose sum is σ = 15445924. Its totient is φ = 15353856.

The previous prime is 15399869. The next prime is 15399929. The reversal of 15399889 is 98899351.

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

It can be written as a sum of positive squares in 2 ways, for example, as 4804864 + 10595025 = 2192^2 + 3255^2 .

It is a cyclic number.

It is not a de Polignac number, because 15399889 - 2¹⁷ = 15268817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15399859) 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, 22512 + ... + 23185.

It is an arithmetic number, because the mean of its divisors is an integer number (3861481).

Almost surely, 2^15399889 is an apocalyptic number.

It is an amenable number.

15399889 is a deficient number, since it is larger than the sum of its proper divisors (46035).

15399889 is an equidigital number, since it uses as much as digits as its factorization.

15399889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46034.

The product of its digits is 699840, while the sum is 52.

The square root of 15399889 is about 3924.2692313347. The cubic root of 15399889 is about 248.7935957192.

The spelling of 15399889 in words is "fifteen million, three hundred ninety-nine thousand, eight hundred eighty-nine".