1221200011120 has 80 divisors (see below), whose sum is σ = 2900155806720. Its totient is φ = 478011739392.

The previous prime is 1221200011063. The next prime is 1221200011123. The reversal of 1221200011120 is 211100021221.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 1221200011120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221200011123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28024069 + ... + 28067611.

It is an arithmetic number, because the mean of its divisors is an integer number (36251947584).

Almost surely, 2^{1221200011120} is an apocalyptic number.

1221200011120 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 1221200011120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1450077903360).

1221200011120 is an abundant number, since it is smaller than the sum of its proper divisors (1678955795600).

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

1221200011120 is a wasteful number, since it uses less digits than its factorization.

1221200011120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51062 (or 51056 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 1221200011120 its reverse (211100021221), we get a palindrome (1432300032341).

The spelling of 1221200011120 in words is "one trillion, two hundred twenty-one billion, two hundred million, eleven thousand, one hundred twenty".