13687997 has 2 divisors, whose sum is σ = 13687998. Its totient is φ = 13687996.

The previous prime is 13687991. The next prime is 13688027. The reversal of 13687997 is 79978631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13623481 + 64516 = 3691^2 + 254^2 .

It is a cyclic number.

It is not a de Polignac number, because 13687997 - 2⁸ = 13687741 is a prime.

It is a super-2 number, since 2×13687997² = 374722523744018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13687991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6843998 + 6843999.

It is an arithmetic number, because the mean of its divisors is an integer number (6843999).

Almost surely, 2^13687997 is an apocalyptic number.

It is an amenable number.

13687997 is a deficient number, since it is larger than the sum of its proper divisors (1).

13687997 is an equidigital number, since it uses as much as digits as its factorization.

13687997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 571536, while the sum is 50.

The square root of 13687997 is about 3699.7293144229. The cubic root of 13687997 is about 239.2103503405.

The spelling of 13687997 in words is "thirteen million, six hundred eighty-seven thousand, nine hundred ninety-seven".