121211111200 has 72 divisors (see below), whose sum is σ = 296427785220. Its totient is φ = 48399052800.

The previous prime is 121211111191. The next prime is 121211111201. The reversal of 121211111200 is 2111112121.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 67552168464 + 53658942736 = 259908^2 + 231644^2 .

It is not an unprimeable number, because it can be changed into a prime (121211111201) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 322060 + ... + 588340.

Almost surely, 2^121211111200 is an apocalyptic number.

121211111200 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 121211111200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (148213892610).

121211111200 is an abundant number, since it is smaller than the sum of its proper divisors (175216674020).

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

121211111200 is a wasteful number, since it uses less digits than its factorization.

121211111200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266870 (or 266857 counting only the distinct ones).

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

Adding to 121211111200 its reverse (2111112121), we get a palindrome (123322223321).

The spelling of 121211111200 in words is "one hundred twenty-one billion, two hundred eleven million, one hundred eleven thousand, two hundred".