121100021200 has 240 divisors, whose sum is σ = 308953350720. Its totient is φ = 45546762240.

The previous prime is 121100021179. The next prime is 121100021267. The reversal of 121100021200 is 2120001121.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 70283539 + ... + 70285261.

It is an arithmetic number, because the mean of its divisors is an integer number (1287305628).

Almost surely, 2^121100021200 is an apocalyptic number.

121100021200 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 121100021200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (154476675360).

121100021200 is an abundant number, since it is smaller than the sum of its proper divisors (187853329520).

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

121100021200 is a wasteful number, since it uses less digits than its factorization.

121100021200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1926 (or 1915 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 121100021200 its reverse (2120001121), we get a palindrome (123220022321).

The spelling of 121100021200 in words is "one hundred twenty-one billion, one hundred million, twenty-one thousand, two hundred".