11123231220 has 36 divisors (see below), whose sum is σ = 33740468580. Its totient is φ = 2966194944.

The previous prime is 11123231219. The next prime is 11123231267. The reversal of 11123231220 is 2213232111.

It can be written as a sum of positive squares in 2 ways, for example, as 8753099364 + 2370131856 = 93558^2 + 48684^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 11123231193 and 11123231202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30897685 + ... + 30898044.

Almost surely, 2^11123231220 is an apocalyptic number.

11123231220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11123231220 is an abundant number, since it is smaller than the sum of its proper divisors (22617237360).

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

11123231220 is a wasteful number, since it uses less digits than its factorization.

11123231220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61795744 (or 61795739 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 11123231220 its reverse (2213232111), we get a palindrome (13336463331).

The spelling of 11123231220 in words is "eleven billion, one hundred twenty-three million, two hundred thirty-one thousand, two hundred twenty".