13988915 has 4 divisors (see below), whose sum is σ = 16786704. Its totient is φ = 11191128.

The previous prime is 13988911. The next prime is 13988927. The reversal of 13988915 is 51988931.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51988931 = 149 ⋅348919.

It is a cyclic number.

It is not a de Polignac number, because 13988915 - 2² = 13988911 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13988911) 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 3 ways as a sum of consecutive naturals, for example, 1398887 + ... + 1398896.

It is an arithmetic number, because the mean of its divisors is an integer number (4196676).

Almost surely, 2^13988915 is an apocalyptic number.

13988915 is a deficient number, since it is larger than the sum of its proper divisors (2797789).

13988915 is an equidigital number, since it uses as much as digits as its factorization.

13988915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2797788.

The product of its digits is 77760, while the sum is 44.

The square root of 13988915 is about 3740.1757980074. The cubic root of 13988915 is about 240.9505990810.

The spelling of 13988915 in words is "thirteen million, nine hundred eighty-eight thousand, nine hundred fifteen".