221201212111 has 12 divisors (see below), whose sum is σ = 245545848072. Its totient is φ = 199100990000.

The previous prime is 221201212013. The next prime is 221201212129. The reversal of 221201212111 is 111212102122.

221201212111 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221201212111 - 2¹¹ = 221201210063 is a prime.

It is a super-2 number, since 2×221201212111² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221201212151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9037825 + ... + 9062266.

It is an arithmetic number, because the mean of its divisors is an integer number (20462154006).

Almost surely, 2^221201212111 is an apocalyptic number.

221201212111 is a deficient number, since it is larger than the sum of its proper divisors (24344635961).

221201212111 is a wasteful number, since it uses less digits than its factorization.

221201212111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18100214 (or 18100203 counting only the distinct ones).

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

Adding to 221201212111 its reverse (111212102122), we get a palindrome (332413314233).

The spelling of 221201212111 in words is "two hundred twenty-one billion, two hundred one million, two hundred twelve thousand, one hundred eleven".