21432764 has 12 divisors (see below), whose sum is σ = 38067624. Its totient is φ = 10556304.

The previous prime is 21432751. The next prime is 21432781. The reversal of 21432764 is 46723412.

It is a congruent number.

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, 39719 + ... + 40254.

It is an arithmetic number, because the mean of its divisors is an integer number (3172302).

Almost surely, 2^21432764 is an apocalyptic number.

It is an amenable number.

21432764 is a deficient number, since it is larger than the sum of its proper divisors (16634860).

21432764 is a wasteful number, since it uses less digits than its factorization.

21432764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80044 (or 80042 counting only the distinct ones).

The product of its digits is 8064, while the sum is 29.

The square root of 21432764 is about 4629.5533261860. The cubic root of 21432764 is about 277.7747256316.

The spelling of 21432764 in words is "twenty-one million, four hundred thirty-two thousand, seven hundred sixty-four".