111212232221 has 16 divisors (see below), whose sum is σ = 119543771520. Its totient is φ = 103103352000.

The previous prime is 111212232217. The next prime is 111212232223. The reversal of 111212232221 is 122232212111.

It is not a de Polignac number, because 111212232221 - 2² = 111212232217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 111212232193 and 111212232202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111212232223) 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, 5102096 + ... + 5123846.

It is an arithmetic number, because the mean of its divisors is an integer number (7471485720).

Almost surely, 2^111212232221 is an apocalyptic number.

It is an amenable number.

111212232221 is a deficient number, since it is larger than the sum of its proper divisors (8331539299).

111212232221 is an frugal number, since it uses more digits than its factorization.

111212232221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21969 (or 21835 counting only the distinct ones).

The product of its digits is 192, while the sum is 20.

Adding to 111212232221 its reverse (122232212111), we get a palindrome (233444444332).

The spelling of 111212232221 in words is "one hundred eleven billion, two hundred twelve million, two hundred thirty-two thousand, two hundred twenty-one".