21368584 has 8 divisors (see below), whose sum is σ = 40066110. Its totient is φ = 10684288.

The previous prime is 21368569. The next prime is 21368591. The reversal of 21368584 is 48586312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19980900 + 1387684 = 4470^2 + 1178^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1335529 + ... + 1335544.

Almost surely, 2^21368584 is an apocalyptic number.

It is an amenable number.

21368584 is a deficient number, since it is larger than the sum of its proper divisors (18697526).

21368584 is a wasteful number, since it uses less digits than its factorization.

21368584 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2671079 (or 2671075 counting only the distinct ones).

The product of its digits is 46080, while the sum is 37.

The square root of 21368584 is about 4622.6165750579. The cubic root of 21368584 is about 277.4971847238.

It can be divided in two parts, 21368 and 584, that added together give a cube (21952 = 28³).

The spelling of 21368584 in words is "twenty-one million, three hundred sixty-eight thousand, five hundred eighty-four".