21121120102100 has 72 divisors (see below), whose sum is σ = 46202616176640. Its totient is φ = 8380310440320.

The previous prime is 21121120102087. The next prime is 21121120102151. The reversal of 21121120102100 is 120102112112.

It is a super-2 number, since 2×21121120102100² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 66885782 + ... + 67200818.

Almost surely, 2^{21121120102100} is an apocalyptic number.

21121120102100 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 21121120102100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23101308088320).

21121120102100 is an abundant number, since it is smaller than the sum of its proper divisors (25081496074540).

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

21121120102100 is a wasteful number, since it uses less digits than its factorization.

21121120102100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320457 (or 320450 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21121120102100 its reverse (120102112112), we get a palindrome (21241222214212).

The spelling of 21121120102100 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twenty million, one hundred two thousand, one hundred".