21539352 has 16 divisors (see below), whose sum is σ = 53848440. Its totient is φ = 7179776.

The previous prime is 21539333. The next prime is 21539363. The reversal of 21539352 is 25393512.

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, 448713 + ... + 448760.

Almost surely, 2^21539352 is an apocalyptic number.

It is an amenable number.

21539352 is an abundant number, since it is smaller than the sum of its proper divisors (32309088).

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

21539352 is a wasteful number, since it uses less digits than its factorization.

21539352 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 897482 (or 897478 counting only the distinct ones).

The product of its digits is 8100, while the sum is 30.

The square root of 21539352 is about 4641.0507430969. The cubic root of 21539352 is about 278.2344346859.

The spelling of 21539352 in words is "twenty-one million, five hundred thirty-nine thousand, three hundred fifty-two".