13997731 has 16 divisors (see below), whose sum is σ = 16213248. Its totient is φ = 11959200.

The previous prime is 13997719. The next prime is 13997741. The reversal of 13997731 is 13779931.

It is a happy number.

It is not a de Polignac number, because 13997731 - 2¹⁵ = 13964963 is a prime.

It is a super-2 number, since 2×13997731² = 391872946296722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13997741) 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 15 ways as a sum of consecutive naturals, for example, 14980 + ... + 15886.

It is an arithmetic number, because the mean of its divisors is an integer number (1013328).

Almost surely, 2^13997731 is an apocalyptic number.

13997731 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

13997731 is a deficient number, since it is larger than the sum of its proper divisors (2215517).

13997731 is a wasteful number, since it uses less digits than its factorization.

13997731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1002.

The product of its digits is 35721, while the sum is 40.

The square root of 13997731 is about 3741.3541666087. The cubic root of 13997731 is about 241.0012052074.

The spelling of 13997731 in words is "thirteen million, nine hundred ninety-seven thousand, seven hundred thirty-one".