21670166652167 has 16 divisors (see below), whose sum is σ = 23905129134240. Its totient is φ = 19479866736000.

The previous prime is 21670166652139. The next prime is 21670166652179. The reversal of 21670166652167 is 76125666107612.

It is not a de Polignac number, because 21670166652167 - 2⁸ = 21670166651911 is a prime.

It is a super-2 number, since 2×21670166652167² (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 (21670166652187) 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, 11757692 + ... + 13475297.

It is an arithmetic number, because the mean of its divisors is an integer number (1494070570890).

Almost surely, 2^{21670166652167} is an apocalyptic number.

21670166652167 is a deficient number, since it is larger than the sum of its proper divisors (2234962482073).

21670166652167 is a wasteful number, since it uses less digits than its factorization.

21670166652167 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25233874.

The product of its (nonzero) digits is 7620480, while the sum is 56.

Subtracting 21670166652167 from its reverse (76125666107612), we obtain a palindrome (54455499455445).

The spelling of 21670166652167 in words is "twenty-one trillion, six hundred seventy billion, one hundred sixty-six million, six hundred fifty-two thousand, one hundred sixty-seven".