21386264 has 8 divisors (see below), whose sum is σ = 40099260. Its totient is φ = 10693128.

The previous prime is 21386263. The next prime is 21386279. The reversal of 21386264 is 46268312.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21386264.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21386263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1336634 + ... + 1336649.

Almost surely, 2^21386264 is an apocalyptic number.

It is an amenable number.

21386264 is a deficient number, since it is larger than the sum of its proper divisors (18712996).

21386264 is a wasteful number, since it uses less digits than its factorization.

21386264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2673289 (or 2673285 counting only the distinct ones).

The product of its digits is 13824, while the sum is 32.

The square root of 21386264 is about 4624.5285165085. The cubic root of 21386264 is about 277.5736957638.

The spelling of 21386264 in words is "twenty-one million, three hundred eighty-six thousand, two hundred sixty-four".