21252885 has 8 divisors (see below), whose sum is σ = 34004640. Its totient is φ = 11334864.

The previous prime is 21252871. The next prime is 21252893. The reversal of 21252885 is 58825212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21252885 - 2⁶ = 21252821 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 708415 + ... + 708444.

It is an arithmetic number, because the mean of its divisors is an integer number (4250580).

Almost surely, 2^21252885 is an apocalyptic number.

It is an amenable number.

21252885 is a deficient number, since it is larger than the sum of its proper divisors (12751755).

21252885 is a wasteful number, since it uses less digits than its factorization.

21252885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1416867.

The product of its digits is 12800, while the sum is 33.

The square root of 21252885 is about 4610.0851402116. The cubic root of 21252885 is about 276.9954471051.

The spelling of 21252885 in words is "twenty-one million, two hundred fifty-two thousand, eight hundred eighty-five".