21696166 has 12 divisors (see below), whose sum is σ = 33324372. Its totient is φ = 10593996.

The previous prime is 21696163. The next prime is 21696167. The reversal of 21696166 is 66169612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21696161) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 765 + ... + 6631.

It is an arithmetic number, because the mean of its divisors is an integer number (2777031).

Almost surely, 2^21696166 is an apocalyptic number.

21696166 is a deficient number, since it is larger than the sum of its proper divisors (11628206).

21696166 is an equidigital number, since it uses as much as digits as its factorization.

21696166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5955 (or 5912 counting only the distinct ones).

The product of its digits is 23328, while the sum is 37.

The square root of 21696166 is about 4657.9143401312. The cubic root of 21696166 is about 278.9080172791.

The spelling of 21696166 in words is "twenty-one million, six hundred ninety-six thousand, one hundred sixty-six".