13906681 has 2 divisors, whose sum is σ = 13906682. Its totient is φ = 13906680.

The previous prime is 13906657. The next prime is 13906687. The reversal of 13906681 is 18660931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13388281 + 518400 = 3659^2 + 720^2 .

It is an emirp because it is prime and its reverse (18660931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13906681 - 2⁵ = 13906649 is a prime.

It is a super-2 number, since 2×13906681² = 386791552871522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (13906687) 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 as a sum of consecutive naturals, namely, 6953340 + 6953341.

It is an arithmetic number, because the mean of its divisors is an integer number (6953341).

Almost surely, 2^13906681 is an apocalyptic number.

It is an amenable number.

13906681 is a deficient number, since it is larger than the sum of its proper divisors (1).

13906681 is an equidigital number, since it uses as much as digits as its factorization.

13906681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 13906681 is about 3729.1662607076. The cubic root of 13906681 is about 240.4775272446.

The spelling of 13906681 in words is "thirteen million, nine hundred six thousand, six hundred eighty-one".