21121001202100 has 36 divisors (see below), whose sum is σ = 46807733738304. Its totient is φ = 8268647277280.

The previous prime is 21121001202097. The next prime is 21121001202109. The reversal of 21121001202100 is 120210012112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21121001202109) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2246910322 + ... + 2246919721.

It is an arithmetic number, because the mean of its divisors is an integer number (1300214826064).

Almost surely, 2^{21121001202100} is an apocalyptic number.

21121001202100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121001202100 is an abundant number, since it is smaller than the sum of its proper divisors (25686732536204).

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

21121001202100 is a wasteful number, since it uses less digits than its factorization.

21121001202100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4493830104 (or 4493830097 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21121001202100 its reverse (120210012112), we get a palindrome (21241211214212).

The spelling of 21121001202100 in words is "twenty-one trillion, one hundred twenty-one billion, one million, two hundred two thousand, one hundred".