13991508 has 48 divisors (see below), whose sum is σ = 36476160. Its totient is φ = 4637952.

The previous prime is 13991507. The next prime is 13991533. The reversal of 13991508 is 80519931.

It is a happy number.

It is a super-2 number, since 2×13991508² = 391524592228128, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13991501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37941 + ... + 38307.

It is an arithmetic number, because the mean of its divisors is an integer number (759920).

Almost surely, 2^13991508 is an apocalyptic number.

13991508 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

13991508 is an abundant number, since it is smaller than the sum of its proper divisors (22484652).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13991508 is a wasteful number, since it uses less digits than its factorization.

13991508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 733 (or 725 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 13991508 is about 3740.5224234056. The cubic root of 13991508 is about 240.9654857801.

The spelling of 13991508 in words is "thirteen million, nine hundred ninety-one thousand, five hundred eight".