22221221200 has 30 divisors (see below), whose sum is σ = 53386484894. Its totient is φ = 8888488320.

The previous prime is 22221221177. The next prime is 22221221201. The reversal of 22221221200 is 212212222.

It can be written as a sum of positive squares in 3 ways, for example, as 5515141696 + 16706079504 = 74264^2 + 129252^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22221221201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 27776127 + ... + 27776926.

Almost surely, 2^22221221200 is an apocalyptic number.

22221221200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22221221200 is an abundant number, since it is smaller than the sum of its proper divisors (31165263694).

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

22221221200 is a wasteful number, since it uses less digits than its factorization.

22221221200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55553071 (or 55553060 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 22221221200 its reverse (212212222), we get a palindrome (22433433422).

The spelling of 22221221200 in words is "twenty-two billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred".