21112212012100 has 288 divisors, whose sum is σ = 52523068308480. Its totient is φ = 7298450880000.

The previous prime is 21112212012091. The next prime is 21112212012103. The reversal of 21112212012100 is 121021221112.

It is not an unprimeable number, because it can be changed into a prime (21112212012103) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 281823249 + ... + 281898151.

It is an arithmetic number, because the mean of its divisors is an integer number (182371764960).

Almost surely, 2^{21112212012100} is an apocalyptic number.

21112212012100 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 21112212012100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26261534154240).

21112212012100 is an abundant number, since it is smaller than the sum of its proper divisors (31410856296380).

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

21112212012100 is a wasteful number, since it uses less digits than its factorization.

21112212012100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75131 (or 75124 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21112212012100 its reverse (121021221112), we get a palindrome (21233233233212).

The spelling of 21112212012100 in words is "twenty-one trillion, one hundred twelve billion, two hundred twelve million, twelve thousand, one hundred".