221121011212111 has 4 divisors (see below), whose sum is σ = 221121044538912. Its totient is φ = 221120977885312.

The previous prime is 221121011212109. The next prime is 221121011212117. The reversal of 221121011212111 is 111212110121122.

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 221121011212111 - 2¹ = 221121011212109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221121011212117) 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, 2948050 + ... + 21235183.

It is an arithmetic number, because the mean of its divisors is an integer number (55280261134728).

Almost surely, 2^{221121011212111} is an apocalyptic number.

221121011212111 is a deficient number, since it is larger than the sum of its proper divisors (33326801).

221121011212111 is an equidigital number, since it uses as much as digits as its factorization.

221121011212111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33326800.

The product of its (nonzero) digits is 32, while the sum is 19.

Adding to 221121011212111 its reverse (111212110121122), we get a palindrome (332333121333233).

It can be divided in two parts, 221121011 and 212111, that added together give a palindrome (221333122).

The spelling of 221121011212111 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, eleven million, two hundred twelve thousand, one hundred eleven".