21221211121100 has 72 divisors (see below), whose sum is σ = 47205562119408. Its totient is φ = 8276191660800.

The previous prime is 21221211120983. The next prime is 21221211121147. The reversal of 21221211121100 is 112111212212.

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, 2035031 + ... + 6825230.

It is an arithmetic number, because the mean of its divisors is an integer number (655632807214).

Almost surely, 2^{21221211121100} is an apocalyptic number.

21221211121100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21221211121100 is an abundant number, since it is smaller than the sum of its proper divisors (25984350998308).

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

21221211121100 is a wasteful number, since it uses less digits than its factorization.

21221211121100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8860875 (or 8860868 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21221211121100 its reverse (112111212212), we get a palindrome (21333322333312).

The spelling of 21221211121100 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred eleven million, one hundred twenty-one thousand, one hundred".