21921852 has 24 divisors (see below), whose sum is σ = 53375616. Its totient is φ = 6989488.

The previous prime is 21921847. The next prime is 21921869. The reversal of 21921852 is 25812912.

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, 39438 + ... + 39989.

It is an arithmetic number, because the mean of its divisors is an integer number (2223984).

Almost surely, 2^21921852 is an apocalyptic number.

It is an amenable number.

21921852 is an abundant number, since it is smaller than the sum of its proper divisors (31453764).

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

21921852 is a wasteful number, since it uses less digits than its factorization.

21921852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79457 (or 79455 counting only the distinct ones).

The product of its digits is 2880, while the sum is 30.

The square root of 21921852 is about 4682.0777439081. The cubic root of 21921852 is about 279.8717610039.

The spelling of 21921852 in words is "twenty-one million, nine hundred twenty-one thousand, eight hundred fifty-two".