21374566 has 16 divisors (see below), whose sum is σ = 33877440. Its totient is φ = 10097920.

The previous prime is 21374543. The next prime is 21374597. The reversal of 21374566 is 66547312.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1195 + ... + 6646.

It is an arithmetic number, because the mean of its divisors is an integer number (2117340).

Almost surely, 2^21374566 is an apocalyptic number.

21374566 is a deficient number, since it is larger than the sum of its proper divisors (12502874).

21374566 is a wasteful number, since it uses less digits than its factorization.

21374566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7919.

The product of its digits is 30240, while the sum is 34.

The square root of 21374566 is about 4623.2635659240. The cubic root of 21374566 is about 277.5230768353.

The spelling of 21374566 in words is "twenty-one million, three hundred seventy-four thousand, five hundred sixty-six".