21254764 has 12 divisors (see below), whose sum is σ = 37332064. Its totient is φ = 10588464.

The previous prime is 21254729. The next prime is 21254789. The reversal of 21254764 is 46745212.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8484 + ... + 10699.

Almost surely, 2^21254764 is an apocalyptic number.

It is an amenable number.

21254764 is a deficient number, since it is larger than the sum of its proper divisors (16077300).

21254764 is a wasteful number, since it uses less digits than its factorization.

21254764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19464 (or 19462 counting only the distinct ones).

The product of its digits is 13440, while the sum is 31.

The square root of 21254764 is about 4610.2889280391. The cubic root of 21254764 is about 277.0036100613.

Adding to 21254764 its reverse (46745212), we get a palindrome (67999976).

It can be divided in two parts, 2125 and 4764, that added together give a square (6889 = 83²).

The spelling of 21254764 in words is "twenty-one million, two hundred fifty-four thousand, seven hundred sixty-four".