13931287 has 2 divisors, whose sum is σ = 13931288. Its totient is φ = 13931286.

The previous prime is 13931221. The next prime is 13931299. The reversal of 13931287 is 78213931.

13931287 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 13931287 - 2²³ = 5542679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13931087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6965643 + 6965644.

It is an arithmetic number, because the mean of its divisors is an integer number (6965644).

Almost surely, 2^13931287 is an apocalyptic number.

13931287 is a deficient number, since it is larger than the sum of its proper divisors (1).

13931287 is an equidigital number, since it uses as much as digits as its factorization.

13931287 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9072, while the sum is 34.

The square root of 13931287 is about 3732.4639315069. The cubic root of 13931287 is about 240.6192745475.

The spelling of 13931287 in words is "thirteen million, nine hundred thirty-one thousand, two hundred eighty-seven".