22521000 has 64 divisors (see below), whose sum is σ = 70274880. Its totient is φ = 6004800.

The previous prime is 22520999. The next prime is 22521041. The reversal of 22521000 is 12522.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 754 + ... + 6753.

It is an arithmetic number, because the mean of its divisors is an integer number (1098045).

Almost surely, 2^22521000 is an apocalyptic number.

22521000 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 22521000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35137440).

22521000 is an abundant number, since it is smaller than the sum of its proper divisors (47753880).

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

22521000 is a wasteful number, since it uses less digits than its factorization.

22521000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7531 (or 7517 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 22521000 is about 4745.6295683502. The cubic root of 22521000 is about 282.3986113829.

Adding to 22521000 its reverse (12522), we get a palindrome (22533522).

The spelling of 22521000 in words is "twenty-two million, five hundred twenty-one thousand".