21667651713 has 24 divisors (see below), whose sum is σ = 32486053600. Its totient is φ = 14432123808.

The previous prime is 21667651637. The next prime is 21667651721. The reversal of 21667651713 is 31715676612.

21667651713 is a `hidden beast` number, since 2 + 1 + 66 + 76 + 517 + 1 + 3 = 666.

It is not a de Polignac number, because 21667651713 - 2¹⁴ = 21667635329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21667651783) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 234858 + ... + 313836.

Almost surely, 2^21667651713 is an apocalyptic number.

It is an amenable number.

21667651713 is a deficient number, since it is larger than the sum of its proper divisors (10818401887).

21667651713 is an equidigital number, since it uses as much as digits as its factorization.

21667651713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80123 (or 80111 counting only the distinct ones).

The product of its digits is 317520, while the sum is 45.

It can be divided in two parts, 21667 and 651713, that added together give a triangular number (673380 = T₁₁₆₀).

The spelling of 21667651713 in words is "twenty-one billion, six hundred sixty-seven million, six hundred fifty-one thousand, seven hundred thirteen".