21785052 has 24 divisors (see below), whose sum is σ = 51666832. Its totient is φ = 7142400.

The previous prime is 21785051. The next prime is 21785059. The reversal of 21785052 is 25058712.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21785051) 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 7 ways as a sum of consecutive naturals, for example, 14149 + ... + 15612.

Almost surely, 2^21785052 is an apocalyptic number.

It is an amenable number.

21785052 is an abundant number, since it is smaller than the sum of its proper divisors (29881780).

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

21785052 is a wasteful number, since it uses less digits than its factorization.

21785052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29829 (or 29827 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 30.

The square root of 21785052 is about 4667.4459825476. The cubic root of 21785052 is about 279.2883800249.

The spelling of 21785052 in words is "twenty-one million, seven hundred eighty-five thousand, fifty-two".