111021212121 has 16 divisors (see below), whose sum is σ = 149999328000. Its totient is φ = 73029835008.

The previous prime is 111021212119. The next prime is 111021212143. The reversal of 111021212121 is 121212120111.

It is a happy number.

It is not a de Polignac number, because 111021212121 - 2¹ = 111021212119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111021212121.

It is not an unprimeable number, because it can be changed into a prime (111021217121) 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, 215905 + ... + 518321.

It is an arithmetic number, because the mean of its divisors is an integer number (9374958000).

Almost surely, 2^111021212121 is an apocalyptic number.

It is an amenable number.

111021212121 is a deficient number, since it is larger than the sum of its proper divisors (38978115879).

111021212121 is a wasteful number, since it uses less digits than its factorization.

111021212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304048.

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

Adding to 111021212121 its reverse (121212120111), we get a palindrome (232233332232).

The spelling of 111021212121 in words is "one hundred eleven billion, twenty-one million, two hundred twelve thousand, one hundred twenty-one".