22121000 has 64 divisors (see below), whose sum is σ = 56496960. Its totient is φ = 8040000.

The previous prime is 22120957. The next prime is 22121003. The reversal of 22121000 is 12122.

It is a Harshad number since it is a multiple of its sum of digits (8).

It is not an unprimeable number, because it can be changed into a prime (22121003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9995 + ... + 12005.

It is an arithmetic number, because the mean of its divisors is an integer number (882765).

Almost surely, 2^22121000 is an apocalyptic number.

22121000 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 22121000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28248480).

22121000 is an abundant number, since it is smaller than the sum of its proper divisors (34375960).

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

22121000 is a wasteful number, since it uses less digits than its factorization.

22121000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2043 (or 2029 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 8.

The square root of 22121000 is about 4703.2967161343. The cubic root of 22121000 is about 280.7167013468.

Adding to 22121000 its reverse (12122), we get a palindrome (22133122).

The spelling of 22121000 in words is "twenty-two million, one hundred twenty-one thousand".