2121012221220 has 36 divisors (see below), whose sum is σ = 6433737071580. Its totient is φ = 565603258944.

The previous prime is 2121012221197. The next prime is 2121012221231. The reversal of 2121012221220 is 221222101212.

It is a happy number.

2121012221220 is a `hidden beast` number, since 2 + 1 + 210 + 12 + 221 + 220 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1334246769216 + 786765452004 = 1155096^2 + 886998^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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 = 2121012221193 and 2121012221202.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5891700435 + ... + 5891700794.

It is an arithmetic number, because the mean of its divisors is an integer number (178714918655).

Almost surely, 2^{2121012221220} is an apocalyptic number.

2121012221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2121012221220 is an abundant number, since it is smaller than the sum of its proper divisors (4312724850360).

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

2121012221220 is a wasteful number, since it uses less digits than its factorization.

2121012221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11783401244 (or 11783401239 counting only the distinct ones).

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

Adding to 2121012221220 its reverse (221222101212), we get a palindrome (2342234322432).

The spelling of 2121012221220 in words is "two trillion, one hundred twenty-one billion, twelve million, two hundred twenty-one thousand, two hundred twenty".