21446866 has 32 divisors (see below), whose sum is σ = 37739520. Its totient is φ = 8952336.

The previous prime is 21446857. The next prime is 21446869. The reversal of 21446866 is 66864412.

It is a super-2 number, since 2×21446866² = 919936122443912, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21446869) 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, 154225 + ... + 154363.

It is an arithmetic number, because the mean of its divisors is an integer number (1179360).

Almost surely, 2^21446866 is an apocalyptic number.

21446866 is a deficient number, since it is larger than the sum of its proper divisors (16292654).

21446866 is a wasteful number, since it uses less digits than its factorization.

21446866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 358.

The product of its digits is 55296, while the sum is 37.

The square root of 21446866 is about 4631.0761168437. The cubic root of 21446866 is about 277.8356342538.

The spelling of 21446866 in words is "twenty-one million, four hundred forty-six thousand, eight hundred sixty-six".