13659881 has 4 divisors (see below), whose sum is σ = 13680852. Its totient is φ = 13638912.

The previous prime is 13659869. The next prime is 13659883. The reversal of 13659881 is 18895631.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5480281 + 8179600 = 2341^2 + 2860^2 .

It is a cyclic number.

It is not a de Polignac number, because 13659881 - 2⁶ = 13659817 is a prime.

It is a super-2 number, since 2×13659881² = 373184697868322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13659883) 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 in 3 ways as a sum of consecutive naturals, for example, 9476 + ... + 10821.

It is an arithmetic number, because the mean of its divisors is an integer number (3420213).

Almost surely, 2^13659881 is an apocalyptic number.

It is an amenable number.

13659881 is a deficient number, since it is larger than the sum of its proper divisors (20971).

13659881 is an equidigital number, since it uses as much as digits as its factorization.

13659881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20970.

The product of its digits is 51840, while the sum is 41.

The square root of 13659881 is about 3695.9276237502. The cubic root of 13659881 is about 239.0464537423.

The spelling of 13659881 in words is "thirteen million, six hundred fifty-nine thousand, eight hundred eighty-one".