21021012221211 has 8 divisors (see below), whose sum is σ = 31142240327760. Its totient is φ = 14014008147456.

The previous prime is 21021012221207. The next prime is 21021012221239. The reversal of 21021012221211 is 11212221012012.

21021012221211 is a `hidden beast` number, since 2 + 10 + 210 + 12 + 221 + 211 = 666.

It is not a de Polignac number, because 21021012221211 - 2² = 21021012221207 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21021012221711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 389278004070 + ... + 389278004123.

It is an arithmetic number, because the mean of its divisors is an integer number (3892780040970).

Almost surely, 2^{21021012221211} is an apocalyptic number.

21021012221211 is a deficient number, since it is larger than the sum of its proper divisors (10121228106549).

21021012221211 is an equidigital number, since it uses as much as digits as its factorization.

21021012221211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778556008202 (or 778556008196 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21021012221211 its reverse (11212221012012), we get a palindrome (32233233233223).

The spelling of 21021012221211 in words is "twenty-one trillion, twenty-one billion, twelve million, two hundred twenty-one thousand, two hundred eleven".