2121102221220 has 72 divisors (see below), whose sum is σ = 6607902255864. Its totient is φ = 550340034048.

The previous prime is 2121102221177. The next prime is 2121102221233. The reversal of 2121102221220 is 221222011212.

It is a happy number.

2121102221220 is a `hidden beast` number, since 2 + 121 + 102 + 221 + 220 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 62543007396 + 2058559213824 = 250086^2 + 1434768^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 2121102221193 and 2121102221202.

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, 159235249 + ... + 159248568.

Almost surely, 2^{2121102221220} is an apocalyptic number.

2121102221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121102221220 is an abundant number, since it is smaller than the sum of its proper divisors (4486800034644).

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

2121102221220 is a wasteful number, since it uses less digits than its factorization.

2121102221220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318483869 (or 318483864 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 2121102221220 its reverse (221222011212), we get a palindrome (2342324232432).

The spelling of 2121102221220 in words is "two trillion, one hundred twenty-one billion, one hundred two million, two hundred twenty-one thousand, two hundred twenty".