21121112211100 has 72 divisors (see below), whose sum is σ = 50029430911488. Its totient is φ = 7675796452800.

The previous prime is 21121112211091. The next prime is 21121112211131. The reversal of 21121112211100 is 111221112112.

It is a super-2 number, since 2×21121112211100² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3925452 + ... + 7592851.

It is an arithmetic number, because the mean of its divisors is an integer number (694853207104).

Almost surely, 2^{21121112211100} is an apocalyptic number.

21121112211100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121112211100 is an abundant number, since it is smaller than the sum of its proper divisors (28908318700388).

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

21121112211100 is a wasteful number, since it uses less digits than its factorization.

21121112211100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11519995 (or 11519988 counting only the distinct ones).

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

Adding to 21121112211100 its reverse (111221112112), we get a palindrome (21232333323212).

It can be divided in two parts, 21 and 121112211100, that added together give a palindrome (121112211121).

The spelling of 21121112211100 in words is "twenty-one trillion, one hundred twenty-one billion, one hundred twelve million, two hundred eleven thousand, one hundred".