21377264 has 20 divisors (see below), whose sum is σ = 41663256. Its totient is φ = 10625472.

The previous prime is 21377249. The next prime is 21377269. The reversal of 21377264 is 46277312.

It is a super-2 number, since 2×21377264² = 913974832251392, which contains 22 as substring.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21377264.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21377269) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1094 + ... + 6629.

Almost surely, 2^21377264 is an apocalyptic number.

It is an amenable number.

21377264 is a deficient number, since it is larger than the sum of its proper divisors (20285992).

21377264 is a wasteful number, since it uses less digits than its factorization.

21377264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7904 (or 7898 counting only the distinct ones).

The product of its digits is 14112, while the sum is 32.

The square root of 21377264 is about 4623.5553419420. Note that the first 3 decimals coincide. The cubic root of 21377264 is about 277.5347531076.

It can be divided in two parts, 213 and 77264, that added together give a palindrome (77477).

The spelling of 21377264 in words is "twenty-one million, three hundred seventy-seven thousand, two hundred sixty-four".