2121101111220 has 576 divisors, whose sum is σ = 7682240434176. Its totient is φ = 433098731520.

The previous prime is 2121101111179. The next prime is 2121101111291. The reversal of 2121101111220 is 221111011212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 2121101111220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 270096814 + ... + 270104666.

It is an arithmetic number, because the mean of its divisors is an integer number (13337222976).

Almost surely, 2^{2121101111220} is an apocalyptic number.

2121101111220 is a gapful number since it is divisible by the number (20) 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 2121101111220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3841120217088).

2121101111220 is an abundant number, since it is smaller than the sum of its proper divisors (5561139322956).

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

2121101111220 is a wasteful number, since it uses less digits than its factorization.

2121101111220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8120 (or 8111 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 2121101111220 its reverse (221111011212), we get a palindrome (2342212122432).

The spelling of 2121101111220 in words is "two trillion, one hundred twenty-one billion, one hundred one million, one hundred eleven thousand, two hundred twenty".