21112212222100 has 18 divisors (see below), whose sum is σ = 45813500522174. Its totient is φ = 8444884888800.

The previous prime is 21112212222089. The next prime is 21112212222107. The reversal of 21112212222100 is 122221221112.

It can be written as a sum of positive squares in 3 ways, for example, as 217823824656 + 20894388397444 = 466716^2 + 4571038^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112212222107) 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, 105561061011 + ... + 105561061210.

Almost surely, 2^{21112212222100} is an apocalyptic number.

21112212222100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21112212222100 is an abundant number, since it is smaller than the sum of its proper divisors (24701288300074).

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

21112212222100 is a wasteful number, since it uses less digits than its factorization.

21112212222100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211122122235 (or 211122122228 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21112212222100 its reverse (122221221112), we get a palindrome (21234433443212).

The spelling of 21112212222100 in words is "twenty-one trillion, one hundred twelve billion, two hundred twelve million, two hundred twenty-two thousand, one hundred".