11212211231 has 4 divisors (see below), whose sum is σ = 12074689032. Its totient is φ = 10349733432.

The previous prime is 11212211221. The next prime is 11212211233. The reversal of 11212211231 is 13211221211.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13211221211 = 47 ⋅281089813.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11212211231 is a prime.

It is a super-2 number, since 2×11212211231² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11212211233) 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, 431238881 + ... + 431238906.

It is an arithmetic number, because the mean of its divisors is an integer number (3018672258).

Almost surely, 2^11212211231 is an apocalyptic number.

11212211231 is a deficient number, since it is larger than the sum of its proper divisors (862477801).

11212211231 is an equidigital number, since it uses as much as digits as its factorization.

11212211231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862477800.

The product of its digits is 48, while the sum is 17.

Adding to 11212211231 its reverse (13211221211), we get a palindrome (24423432442).

The spelling of 11212211231 in words is "eleven billion, two hundred twelve million, two hundred eleven thousand, two hundred thirty-one".