20201210221 has 4 divisors (see below), whose sum is σ = 20229307200. Its totient is φ = 20173113244.

The previous prime is 20201210213. The next prime is 20201210261. The reversal of 20201210221 is 12201210202.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20201210221 - 2³ = 20201210213 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 (20201210261) 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, 14047411 + ... + 14048848.

It is an arithmetic number, because the mean of its divisors is an integer number (5057326800).

Almost surely, 2^20201210221 is an apocalyptic number.

It is an amenable number.

20201210221 is a deficient number, since it is larger than the sum of its proper divisors (28096979).

20201210221 is an equidigital number, since it uses as much as digits as its factorization.

20201210221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28096978.

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

Adding to 20201210221 its reverse (12201210202), we get a palindrome (32402420423).

The spelling of 20201210221 in words is "twenty billion, two hundred one million, two hundred ten thousand, two hundred twenty-one".