13681854521 has 2 divisors, whose sum is σ = 13681854522. Its totient is φ = 13681854520.

The previous prime is 13681854499. The next prime is 13681854539. The reversal of 13681854521 is 12545818631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13003981225 + 677873296 = 114035^2 + 26036^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13681854521 is a prime.

It is not a weakly prime, because it can be changed into another prime (13681854551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6840927260 + 6840927261.

It is an arithmetic number, because the mean of its divisors is an integer number (6840927261).

Almost surely, 2^13681854521 is an apocalyptic number.

It is an amenable number.

13681854521 is a deficient number, since it is larger than the sum of its proper divisors (1).

13681854521 is an equidigital number, since it uses as much as digits as its factorization.

13681854521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 230400, while the sum is 44.

The spelling of 13681854521 in words is "thirteen billion, six hundred eighty-one million, eight hundred fifty-four thousand, five hundred twenty-one".