2220120121 has 4 divisors (see below), whose sum is σ = 2224106532. Its totient is φ = 2216133712.

The previous prime is 2220120073. The next prime is 2220120137. The reversal of 2220120121 is 1210210222.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 137475625 + 2082644496 = 11725^2 + 45636^2 .

It is a cyclic number.

It is not a de Polignac number, because 2220120121 - 2⁹ = 2220119609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2220120191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1992370 + ... + 1993483.

It is an arithmetic number, because the mean of its divisors is an integer number (556026633).

Almost surely, 2^2220120121 is an apocalyptic number.

It is an amenable number.

2220120121 is a deficient number, since it is larger than the sum of its proper divisors (3986411).

2220120121 is an equidigital number, since it uses as much as digits as its factorization.

2220120121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3986410.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 2220120121 is about 47118.1506534372. The cubic root of 2220120121 is about 1304.5442781752.

Adding to 2220120121 its reverse (1210210222), we get a palindrome (3430330343).

The spelling of 2220120121 in words is "two billion, two hundred twenty million, one hundred twenty thousand, one hundred twenty-one".