21122111100100 has 288 divisors, whose sum is σ = 48932430624000. Its totient is φ = 7891594905600.

The previous prime is 21122111100091. The next prime is 21122111100133. The reversal of 21122111100100 is 100111122112.

It is a happy number.

It is a super-2 number, since 2×21122111100100² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 33474026785 + ... + 33474027415.

It is an arithmetic number, because the mean of its divisors is an integer number (169904273000).

Almost surely, 2^{21122111100100} is an apocalyptic number.

21122111100100 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 21122111100100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24466215312000).

21122111100100 is an abundant number, since it is smaller than the sum of its proper divisors (27810319523900).

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

21122111100100 is a wasteful number, since it uses less digits than its factorization.

21122111100100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1503 (or 1496 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21122111100100 its reverse (100111122112), we get a palindrome (21222222222212).

The spelling of 21122111100100 in words is "twenty-one trillion, one hundred twenty-two billion, one hundred eleven million, one hundred thousand, one hundred".