20101221210211 has 4 divisors (see below), whose sum is σ = 20101894354672. Its totient is φ = 20100548065752.

The previous prime is 20101221210199. The next prime is 20101221210227. The reversal of 20101221210211 is 11201212210102.

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

It is a cyclic number.

It is not a de Polignac number, because 20101221210211 - 2²⁹ = 20100684339299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20101221270211) 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, 336527436 + ... + 336587161.

It is an arithmetic number, because the mean of its divisors is an integer number (5025473588668).

Almost surely, 2^{20101221210211} is an apocalyptic number.

20101221210211 is a deficient number, since it is larger than the sum of its proper divisors (673144461).

20101221210211 is an equidigital number, since it uses as much as digits as its factorization.

20101221210211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673144460.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 20101221210211 its reverse (11201212210102), we get a palindrome (31302433420313).

The spelling of 20101221210211 in words is "twenty trillion, one hundred one billion, two hundred twenty-one million, two hundred ten thousand, two hundred eleven".