21462564 has 12 divisors (see below), whose sum is σ = 50079344. Its totient is φ = 7154184.

The previous prime is 21462563. The next prime is 21462569. The reversal of 21462564 is 46526412.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (21462563) by changing a digit.

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, 894262 + ... + 894285.

Almost surely, 2^21462564 is an apocalyptic number.

It is an amenable number.

21462564 is an abundant number, since it is smaller than the sum of its proper divisors (28616780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21462564 is a wasteful number, since it uses less digits than its factorization.

21462564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1788554 (or 1788552 counting only the distinct ones).

The product of its digits is 11520, while the sum is 30.

The square root of 21462564 is about 4632.7706612782. The cubic root of 21462564 is about 277.9034048408.

Adding to 21462564 its reverse (46526412), we get a palindrome (67988976).

The spelling of 21462564 in words is "twenty-one million, four hundred sixty-two thousand, five hundred sixty-four".