21529364 has 6 divisors (see below), whose sum is σ = 37676394. Its totient is φ = 10764680.

The previous prime is 21529349. The next prime is 21529393. The reversal of 21529364 is 46392512.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20611600 + 917764 = 4540^2 + 958^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21529364.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2691167 + ... + 2691174.

It is an arithmetic number, because the mean of its divisors is an integer number (6279399).

Almost surely, 2^21529364 is an apocalyptic number.

It is an amenable number.

21529364 is a deficient number, since it is larger than the sum of its proper divisors (16147030).

21529364 is a wasteful number, since it uses less digits than its factorization.

21529364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5382345 (or 5382343 counting only the distinct ones).

The product of its digits is 12960, while the sum is 32.

The square root of 21529364 is about 4639.9745688958. The cubic root of 21529364 is about 278.1914213957.

The spelling of 21529364 in words is "twenty-one million, five hundred twenty-nine thousand, three hundred sixty-four".