13971931 has 2 divisors, whose sum is σ = 13971932. Its totient is φ = 13971930.

The previous prime is 13971929. The next prime is 13971941. The reversal of 13971931 is 13917931.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 13971931 - 2¹ = 13971929 is a prime.

It is a super-2 number, since 2×13971931² = 390429711737522, which contains 22 as substring.

Together with 13971929, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (13971911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6985965 + 6985966.

It is an arithmetic number, because the mean of its divisors is an integer number (6985966).

Almost surely, 2^13971931 is an apocalyptic number.

13971931 is a deficient number, since it is larger than the sum of its proper divisors (1).

13971931 is an equidigital number, since it uses as much as digits as its factorization.

13971931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5103, while the sum is 34.

The square root of 13971931 is about 3737.9046269267. The cubic root of 13971931 is about 240.8530465486.

The spelling of 13971931 in words is "thirteen million, nine hundred seventy-one thousand, nine hundred thirty-one".