21725892 has 72 divisors (see below), whose sum is σ = 60365760. Its totient is φ = 6557760.

The previous prime is 21725863. The next prime is 21725897. The reversal of 21725892 is 29852712.

21725892 is a `hidden beast` number, since 2 + 1 + 72 + 589 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21725897) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15042 + ... + 16422.

Almost surely, 2^21725892 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21725892, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30182880).

21725892 is an abundant number, since it is smaller than the sum of its proper divisors (38639868).

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

21725892 is a wasteful number, since it uses less digits than its factorization.

21725892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1433 (or 1428 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 21725892 is about 4661.1041610331. The cubic root of 21725892 is about 279.0353367968.

The spelling of 21725892 in words is "twenty-one million, seven hundred twenty-five thousand, eight hundred ninety-two".