13661940681 has 32 divisors (see below), whose sum is σ = 20391969920. Its totient is φ = 9039693312.

The previous prime is 13661940679. The next prime is 13661940713. The reversal of 13661940681 is 18604916631.

13661940681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 13661940681 - 2¹ = 13661940679 is a prime.

It is a super-2 number, since 2×13661940681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13661940581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4122081 + ... + 4125393.

It is an arithmetic number, because the mean of its divisors is an integer number (637249060).

Almost surely, 2^13661940681 is an apocalyptic number.

It is an amenable number.

13661940681 is a deficient number, since it is larger than the sum of its proper divisors (6730029239).

13661940681 is a wasteful number, since it uses less digits than its factorization.

13661940681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4422 (or 4416 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 13661940681 in words is "thirteen billion, six hundred sixty-one million, nine hundred forty thousand, six hundred eighty-one".