20201201221 has 4 divisors (see below), whose sum is σ = 20428181100. Its totient is φ = 19974221344.

The previous prime is 20201201203. The next prime is 20201201239. The reversal of 20201201221 is 12210210202.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (20201201203) and next prime (20201201239).

It can be written as a sum of positive squares in 2 ways, for example, as 9046672996 + 11154528225 = 95114^2 + 105615^2 .

It is a cyclic number.

It is not a de Polignac number, because 20201201221 - 2²³ = 20192812613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201201291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113489806 + ... + 113489983.

It is an arithmetic number, because the mean of its divisors is an integer number (5107045275).

Almost surely, 2^20201201221 is an apocalyptic number.

It is an amenable number.

20201201221 is a deficient number, since it is larger than the sum of its proper divisors (226979879).

20201201221 is an equidigital number, since it uses as much as digits as its factorization.

20201201221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226979878.

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

Adding to 20201201221 its reverse (12210210202), we get a palindrome (32411411423).

The spelling of 20201201221 in words is "twenty billion, two hundred one million, two hundred one thousand, two hundred twenty-one".