22221212100 has 72 divisors (see below), whose sum is σ = 66031065408. Its totient is φ = 5765500800.

The previous prime is 22221212099. The next prime is 22221212113. The reversal of 22221212100 is 121212222.

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

It is a self number, because there is not a number n which added to its sum of digits gives 22221212100.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 989856 + ... + 1012055.

Almost surely, 2^22221212100 is an apocalyptic number.

22221212100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

22221212100 is an abundant number, since it is smaller than the sum of its proper divisors (43809853308).

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

22221212100 is a wasteful number, since it uses less digits than its factorization.

22221212100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2001965 (or 2001958 counting only the distinct ones).

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

Adding to 22221212100 its reverse (121212222), we get a palindrome (22342424322).

It can be divided in two parts, 22 and 221212100, that added together give a palindrome (221212122).

The spelling of 22221212100 in words is "twenty-two billion, two hundred twenty-one million, two hundred twelve thousand, one hundred".