21211101111100 has 144 divisors (see below), whose sum is σ = 48059832029440. Its totient is φ = 8116576358400.

The previous prime is 21211101111077. The next prime is 21211101111103. The reversal of 21211101111100 is 111110111212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211101111103) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 146238214 + ... + 146383186.

Almost surely, 2^{21211101111100} is an apocalyptic number.

21211101111100 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 21211101111100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24029916014720).

21211101111100 is an abundant number, since it is smaller than the sum of its proper divisors (26848730918340).

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

21211101111100 is a wasteful number, since it uses less digits than its factorization.

21211101111100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145560 (or 145553 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 21211101111100 its reverse (111110111212), we get a palindrome (21322211222312).

The spelling of 21211101111100 in words is "twenty-one trillion, two hundred eleven billion, one hundred one million, one hundred eleven thousand, one hundred".