20201210210221 has 4 divisors (see below), whose sum is σ = 20201225353792. Its totient is φ = 20201195066652.

The previous prime is 20201210210219. The next prime is 20201210210243. The reversal of 20201210210221 is 12201201210202.

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 20201210210221 - 2¹ = 20201210210219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20201210210195 and 20201210210204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201210210261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5354355 + ... + 8310928.

It is an arithmetic number, because the mean of its divisors is an integer number (5050306338448).

Almost surely, 2^{20201210210221} is an apocalyptic number.

It is an amenable number.

20201210210221 is a deficient number, since it is larger than the sum of its proper divisors (15143571).

20201210210221 is a wasteful number, since it uses less digits than its factorization.

20201210210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15143570.

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

Adding to 20201210210221 its reverse (12201201210202), we get a palindrome (32402411420423).

The spelling of 20201210210221 in words is "twenty trillion, two hundred one billion, two hundred ten million, two hundred ten thousand, two hundred twenty-one".