13931281 has 16 divisors (see below), whose sum is σ = 17740800. Its totient is φ = 10640448.

The previous prime is 13931221. The next prime is 13931287. The reversal of 13931281 is 18213931.

13931281 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

13931281 is a nontrivial binomial coefficient, being equal to C(5279, 2).

It is not a de Polignac number, because 13931281 - 2⁷ = 13931153 is a prime.

It is a super-2 number, since 2×13931281² = 388161180601922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13931287) 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, 1 + ... + 5278.

It is an arithmetic number, because the mean of its divisors is an integer number (1108800).

Almost surely, 2^13931281 is an apocalyptic number.

13931281 is the 5278-th triangular number.

13931281 is the 1760-th centered nonagonal number.

It is an amenable number.

13931281 is a deficient number, since it is larger than the sum of its proper divisors (3809519).

13931281 is a wasteful number, since it uses less digits than its factorization.

13931281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5328.

The product of its digits is 1296, while the sum is 28.

The square root of 13931281 is about 3732.4631277482. The cubic root of 13931281 is about 240.6192400038.

The spelling of 13931281 in words is "thirteen million, nine hundred thirty-one thousand, two hundred eighty-one".