121111212100 has 72 divisors (see below), whose sum is σ = 272080585728. Its totient is φ = 46764115200.

The previous prime is 121111212091. The next prime is 121111212107. The reversal of 121111212100 is 1212111121.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (121111212107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 166605 + ... + 519595.

It is an arithmetic number, because the mean of its divisors is an integer number (3778897024).

Almost surely, 2^121111212100 is an apocalyptic number.

121111212100 is a gapful number since it is divisible by the number (10) 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 121111212100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (136040292864).

121111212100 is an abundant number, since it is smaller than the sum of its proper divisors (150969373628).

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

121111212100 is a wasteful number, since it uses less digits than its factorization.

121111212100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 353125 (or 353118 counting only the distinct ones).

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

Adding to 121111212100 its reverse (1212111121), we get a palindrome (122323323221).

The spelling of 121111212100 in words is "one hundred twenty-one billion, one hundred eleven million, two hundred twelve thousand, one hundred".