21925280 has 96 divisors (see below), whose sum is σ = 56899584. Its totient is φ = 7934976.

The previous prime is 21925273. The next prime is 21925289. The reversal of 21925280 is 8252912.

It is not an unprimeable number, because it can be changed into a prime (21925289) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 172577 + ... + 172703.

It is an arithmetic number, because the mean of its divisors is an integer number (592704).

Almost surely, 2^21925280 is an apocalyptic number.

21925280 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21925280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28449792).

21925280 is an abundant number, since it is smaller than the sum of its proper divisors (34974304).

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

21925280 is a wasteful number, since it uses less digits than its factorization.

21925280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 21925280 is about 4682.4438063900. The cubic root of 21925280 is about 279.8863484331.

The spelling of 21925280 in words is "twenty-one million, nine hundred twenty-five thousand, two hundred eighty".