22281000 has 128 divisors (see below), whose sum is σ = 79522560. Its totient is φ = 5088000.

The previous prime is 22280989. The next prime is 22281023. The reversal of 22281000 is 18222.

It is a super-2 number, since 2×22281000² = 992885922000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20470 + ... + 21530.

It is an arithmetic number, because the mean of its divisors is an integer number (621270).

Almost surely, 2^22281000 is an apocalyptic number.

22281000 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 22281000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39761280).

22281000 is an abundant number, since it is smaller than the sum of its proper divisors (57241560).

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

22281000 is a wasteful number, since it uses less digits than its factorization.

22281000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1092 (or 1078 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 22281000 is about 4720.2754156935. The cubic root of 22281000 is about 281.3918790331.

Adding to 22281000 its reverse (18222), we get a palindrome (22299222).

The spelling of 22281000 in words is "twenty-two million, two hundred eighty-one thousand".