21967564 has 12 divisors (see below), whose sum is σ = 39073888. Its totient is φ = 10803600.

The previous prime is 21967549. The next prime is 21967579. The reversal of 21967564 is 46576912.

It is an interprime number because it is at equal distance from previous prime (21967549) and next prime (21967579).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44772 + ... + 45259.

Almost surely, 2^21967564 is an apocalyptic number.

It is an amenable number.

21967564 is a deficient number, since it is larger than the sum of its proper divisors (17106324).

21967564 is a wasteful number, since it uses less digits than its factorization.

21967564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90096 (or 90094 counting only the distinct ones).

The product of its digits is 90720, while the sum is 40.

The square root of 21967564 is about 4686.9567951924. The cubic root of 21967564 is about 280.0661578365.

The spelling of 21967564 in words is "twenty-one million, nine hundred sixty-seven thousand, five hundred sixty-four".