20921892 has 12 divisors (see below), whose sum is σ = 48817776. Its totient is φ = 6973960.

The previous prime is 20921867. The next prime is 20921897. The reversal of 20921892 is 29812902.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (20921897) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 871734 + ... + 871757.

It is an arithmetic number, because the mean of its divisors is an integer number (4068148).

Almost surely, 2^20921892 is an apocalyptic number.

It is an amenable number.

20921892 is an abundant number, since it is smaller than the sum of its proper divisors (27895884).

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

20921892 is a wasteful number, since it uses less digits than its factorization.

20921892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1743498 (or 1743496 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 20921892 is about 4574.0454741946. The cubic root of 20921892 is about 275.5499386308.

The spelling of 20921892 in words is "twenty million, nine hundred twenty-one thousand, eight hundred ninety-two".