121212211100 has 72 divisors (see below), whose sum is σ = 265650945168. Its totient is φ = 48004070400.

The previous prime is 121212211079. The next prime is 121212211117. The reversal of 121212211100 is 1112212121.

It is a zygodrome in base 2.

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, 4429460 + ... + 4456740.

Almost surely, 2^121212211100 is an apocalyptic number.

121212211100 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 121212211100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132825472584).

121212211100 is an abundant number, since it is smaller than the sum of its proper divisors (144438734068).

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

121212211100 is a wasteful number, since it uses less digits than its factorization.

121212211100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27735 (or 27728 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 121212211100 its reverse (1112212121), we get a palindrome (122324423221).

The spelling of 121212211100 in words is "one hundred twenty-one billion, two hundred twelve million, two hundred eleven thousand, one hundred".