21000112012100 has 144 divisors (see below), whose sum is σ = 50093015716800. Its totient is φ = 7594121925120.

The previous prime is 21000112012079. The next prime is 21000112012129. The reversal of 21000112012100 is 121021100012.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 20123387 + ... + 21141213.

It is an arithmetic number, because the mean of its divisors is an integer number (347868164700).

Almost surely, 2^{21000112012100} is an apocalyptic number.

21000112012100 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 21000112012100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25046507858400).

21000112012100 is an abundant number, since it is smaller than the sum of its proper divisors (29092903704700).

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

21000112012100 is a wasteful number, since it uses less digits than its factorization.

21000112012100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018182 (or 1018175 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21000112012100 its reverse (121021100012), we get a palindrome (21121133112112).

The spelling of 21000112012100 in words is "twenty-one trillion, one hundred twelve million, twelve thousand, one hundred".