13665656639 has 2 divisors, whose sum is σ = 13665656640. Its totient is φ = 13665656638.

The previous prime is 13665656621. The next prime is 13665656647. The reversal of 13665656639 is 93665656631.

It is a strong prime.

It is an emirp because it is prime and its reverse (93665656631) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13665656639 - 2⁸ = 13665656383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13665656239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6832828319 + 6832828320.

It is an arithmetic number, because the mean of its divisors is an integer number (6832828320).

Almost surely, 2^13665656639 is an apocalyptic number.

13665656639 is a deficient number, since it is larger than the sum of its proper divisors (1).

13665656639 is an equidigital number, since it uses as much as digits as its factorization.

13665656639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15746400, while the sum is 56.

The spelling of 13665656639 in words is "thirteen billion, six hundred sixty-five million, six hundred fifty-six thousand, six hundred thirty-nine".