15613989 has 8 divisors (see below), whose sum is σ = 21326592. Its totient is φ = 10155360.

The previous prime is 15613979. The next prime is 15614003. The reversal of 15613989 is 98931651.

15613989 = 597² + 598² + ... + 637².

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 15613989 - 2⁸ = 15613733 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 15613989.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15613909) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63349 + ... + 63594.

It is an arithmetic number, because the mean of its divisors is an integer number (2665824).

Almost surely, 2^15613989 is an apocalyptic number.

It is an amenable number.

15613989 is a deficient number, since it is larger than the sum of its proper divisors (5712603).

15613989 is a wasteful number, since it uses less digits than its factorization.

15613989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126987.

The product of its digits is 58320, while the sum is 42.

The square root of 15613989 is about 3951.4540361745. The cubic root of 15613989 is about 249.9412608666.

The spelling of 15613989 in words is "fifteen million, six hundred thirteen thousand, nine hundred eighty-nine".