13993560661 has 2 divisors, whose sum is σ = 13993560662. Its totient is φ = 13993560660.

The previous prime is 13993560619. The next prime is 13993560671. The reversal of 13993560661 is 16606539931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12610167025 + 1383393636 = 112295^2 + 37194^2 .

It is an emirp because it is prime and its reverse (16606539931) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13993560661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13993560671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6996780330 + 6996780331.

It is an arithmetic number, because the mean of its divisors is an integer number (6996780331).

Almost surely, 2^13993560661 is an apocalyptic number.

It is an amenable number.

13993560661 is a deficient number, since it is larger than the sum of its proper divisors (1).

13993560661 is an equidigital number, since it uses as much as digits as its factorization.

13993560661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 787320, while the sum is 49.

The spelling of 13993560661 in words is "thirteen billion, nine hundred ninety-three million, five hundred sixty thousand, six hundred sixty-one".