13366438991361 has 24 divisors (see below), whose sum is σ = 20428542386720. Its totient is φ = 8398220714496.

The previous prime is 13366438991309. The next prime is 13366438991383. The reversal of 13366438991361 is 16319983466331.

13366438991361 is a `hidden beast` number, since 1 + 3 + 3 + 66 + 438 + 9 + 9 + 136 + 1 = 666.

It is not a de Polignac number, because 13366438991361 - 2²⁶ = 13366371882497 is a prime.

It is a hoax number, since the sum of its digits (63) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13366438951361) 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 23 ways as a sum of consecutive naturals, for example, 202470391 + ... + 202536396.

Almost surely, 2^{13366438991361} is an apocalyptic number.

It is an amenable number.

13366438991361 is a deficient number, since it is larger than the sum of its proper divisors (7062103395359).

13366438991361 is a wasteful number, since it uses less digits than its factorization.

13366438991361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405007005 (or 405007002 counting only the distinct ones).

The product of its digits is 45349632, while the sum is 63.

It can be divided in two parts, 133664 and 38991361, that added together give a square (39125025 = 6255²).

The spelling of 13366438991361 in words is "thirteen trillion, three hundred sixty-six billion, four hundred thirty-eight million, nine hundred ninety-one thousand, three hundred sixty-one".