221101212221211 has 16 divisors (see below), whose sum is σ = 337585946310144. Its totient is φ = 126092369815104.

The previous prime is 221101212221189. The next prime is 221101212221221. The reversal of 221101212221211 is 112122212101122.

It is not a de Polignac number, because 221101212221211 - 2⁶ = 221101212221147 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (221101212221221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10465823586 + ... + 10465844711.

It is an arithmetic number, because the mean of its divisors is an integer number (21099121644384).

Almost surely, 2^{221101212221211} is an apocalyptic number.

221101212221211 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

221101212221211 is a deficient number, since it is larger than the sum of its proper divisors (116484734088933).

221101212221211 is a wasteful number, since it uses less digits than its factorization.

221101212221211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20931668810.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 221101212221211 its reverse (112122212101122), we get a palindrome (333223424322333).

The spelling of 221101212221211 in words is "two hundred twenty-one trillion, one hundred one billion, two hundred twelve million, two hundred twenty-one thousand, two hundred eleven".