221220211121111 has 8 divisors (see below), whose sum is σ = 227072977628448. Its totient is φ = 215439257700000.

The previous prime is 221220211121081. The next prime is 221220211121123. The reversal of 221220211121111 is 111121112022122.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221220211121111 - 2²⁶ = 221220144012247 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 (221220211121131) 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, 17953265315 + ... + 17953277636.

It is an arithmetic number, because the mean of its divisors is an integer number (28384122203556).

Almost surely, 2^{221220211121111} is an apocalyptic number.

221220211121111 is a deficient number, since it is larger than the sum of its proper divisors (5852766507337).

221220211121111 is a wasteful number, since it uses less digits than its factorization.

221220211121111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35906543113.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 221220211121111 its reverse (111121112022122), we get a palindrome (332341323143233).

The spelling of 221220211121111 in words is "two hundred twenty-one trillion, two hundred twenty billion, two hundred eleven million, one hundred twenty-one thousand, one hundred eleven".