1311123228 has 12 divisors (see below), whose sum is σ = 3059287560. Its totient is φ = 437041072.

The previous prime is 1311123227. The next prime is 1311123271. The reversal of 1311123228 is 8223211131.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×1311123228² = 3438088238002279968, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1311123198 and 1311123207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311123221) 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, 54630123 + ... + 54630146.

It is an arithmetic number, because the mean of its divisors is an integer number (254940630).

Almost surely, 2^1311123228 is an apocalyptic number.

It is an amenable number.

1311123228 is an abundant number, since it is smaller than the sum of its proper divisors (1748164332).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1311123228 is a wasteful number, since it uses less digits than its factorization.

1311123228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109260276 (or 109260274 counting only the distinct ones).

The product of its digits is 576, while the sum is 24.

The square root of 1311123228 is about 36209.4356211195. The cubic root of 1311123228 is about 1094.4968193312.

Adding to 1311123228 its reverse (8223211131), we get a palindrome (9534334359).

The spelling of 1311123228 in words is "one billion, three hundred eleven million, one hundred twenty-three thousand, two hundred twenty-eight".