21916684 has 6 divisors (see below), whose sum is σ = 38354204. Its totient is φ = 10958340.

The previous prime is 21916669. The next prime is 21916753. The reversal of 21916684 is 48661912.

It is a happy 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 as a sum of consecutive naturals, namely, 2739582 + ... + 2739589.

Almost surely, 2^21916684 is an apocalyptic number.

It is an amenable number.

21916684 is a deficient number, since it is larger than the sum of its proper divisors (16437520).

21916684 is a wasteful number, since it uses less digits than its factorization.

21916684 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5479175 (or 5479173 counting only the distinct ones).

The product of its digits is 20736, while the sum is 37.

The square root of 21916684 is about 4681.5258196447. The cubic root of 21916684 is about 279.8497663455.

The spelling of 21916684 in words is "twenty-one million, nine hundred sixteen thousand, six hundred eighty-four".