13666644666631 has 16 divisors (see below), whose sum is σ = 15058214276256. Its totient is φ = 12299958000000.

The previous prime is 13666644666629. The next prime is 13666644666641.

13666644666631 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 13666644666631 - 2¹ = 13666644666629 is a prime.

It is a super-2 number, since 2×13666644666631² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13666644666641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10378801 + ... + 11621221.

It is an arithmetic number, because the mean of its divisors is an integer number (941138392266).

Almost surely, 2^{13666644666631} is an apocalyptic number.

13666644666631 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

13666644666631 is a deficient number, since it is larger than the sum of its proper divisors (1391569609625).

13666644666631 is a wasteful number, since it uses less digits than its factorization.

13666644666631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1252434.

The product of its digits is 241864704, while the sum is 64.

The spelling of 13666644666631 in words is "thirteen trillion, six hundred sixty-six billion, six hundred forty-four million, six hundred sixty-six thousand, six hundred thirty-one".