221012111121 has 32 divisors (see below), whose sum is σ = 303061493760. Its totient is φ = 143197194816.

The previous prime is 221012111113. The next prime is 221012111141. The reversal of 221012111121 is 121111210122.

It is a happy number.

It is not a de Polignac number, because 221012111121 - 2³ = 221012111113 is a prime.

It is a super-3 number, since 3×221012111121³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 221012111121.

It is not an unprimeable number, because it can be changed into a prime (221012111101) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 66829950 + ... + 66833256.

It is an arithmetic number, because the mean of its divisors is an integer number (9470671680).

Almost surely, 2^221012111121 is an apocalyptic number.

It is an amenable number.

221012111121 is a deficient number, since it is larger than the sum of its proper divisors (82049382639).

221012111121 is a wasteful number, since it uses less digits than its factorization.

221012111121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6533.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 221012111121 its reverse (121111210122), we get a palindrome (342123321243).

Subtracting from 221012111121 its reverse (121111210122), we obtain a palindrome (99900900999).

The spelling of 221012111121 in words is "two hundred twenty-one billion, twelve million, one hundred eleven thousand, one hundred twenty-one".