20201220222173 has 2 divisors, whose sum is σ = 20201220222174. Its totient is φ = 20201220222172.

The previous prime is 20201220222097. The next prime is 20201220222389. The reversal of 20201220222173 is 37122202210202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19592503500964 + 608716721209 = 4426342^2 + 780203^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20201220222173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20201220222773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10100610111086 + 10100610111087.

It is an arithmetic number, because the mean of its divisors is an integer number (10100610111087).

Almost surely, 2^{20201220222173} is an apocalyptic number.

It is an amenable number.

20201220222173 is a deficient number, since it is larger than the sum of its proper divisors (1).

20201220222173 is an equidigital number, since it uses as much as digits as its factorization.

20201220222173 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 26.

Adding to 20201220222173 its reverse (37122202210202), we get a palindrome (57323422432375).

The spelling of 20201220222173 in words is "twenty trillion, two hundred one billion, two hundred twenty million, two hundred twenty-two thousand, one hundred seventy-three".