20202222121 has 4 divisors (see below), whose sum is σ = 20898850500. Its totient is φ = 19505593744.

The previous prime is 20202222059. The next prime is 20202222127. The reversal of 20202222121 is 12122220202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12122220202 = 2 ⋅6061110101.

It can be written as a sum of positive squares in 2 ways, for example, as 17177772096 + 3024450025 = 131064^2 + 54995^2 .

It is a cyclic number.

It is not a de Polignac number, because 20202222121 - 2¹⁹ = 20201697833 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20202222095 and 20202222104.

It is not an unprimeable number, because it can be changed into a prime (20202222127) 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, 348314146 + ... + 348314203.

It is an arithmetic number, because the mean of its divisors is an integer number (5224712625).

Almost surely, 2^20202222121 is an apocalyptic number.

It is an amenable number.

20202222121 is a deficient number, since it is larger than the sum of its proper divisors (696628379).

20202222121 is an equidigital number, since it uses as much as digits as its factorization.

20202222121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 696628378.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 20202222121 its reverse (12122220202), we get a palindrome (32324442323).

The spelling of 20202222121 in words is "twenty billion, two hundred two million, two hundred twenty-two thousand, one hundred twenty-one".