220102121221 has 4 divisors (see below), whose sum is σ = 220725640332. Its totient is φ = 219478602112.

The previous prime is 220102121219. The next prime is 220102121227. The reversal of 220102121221 is 122121201022.

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 69743528100 + 150358593121 = 264090^2 + 387761^2 .

It is a cyclic number.

It is not a de Polignac number, because 220102121221 - 2¹ = 220102121219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 220102121195 and 220102121204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220102121227) 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, 311759026 + ... + 311759731.

It is an arithmetic number, because the mean of its divisors is an integer number (55181410083).

Almost surely, 2^220102121221 is an apocalyptic number.

It is an amenable number.

220102121221 is a deficient number, since it is larger than the sum of its proper divisors (623519111).

220102121221 is an equidigital number, since it uses as much as digits as its factorization.

220102121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 623519110.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 220102121221 its reverse (122121201022), we get a palindrome (342223322243).

The spelling of 220102121221 in words is "two hundred twenty billion, one hundred two million, one hundred twenty-one thousand, two hundred twenty-one".