11123212013 has 4 divisors (see below), whose sum is σ = 11777518620. Its totient is φ = 10468905408.

The previous prime is 11123211989. The next prime is 11123212019. The reversal of 11123212013 is 31021232111.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31021232111 = 29 ⋅1069697659.

It can be written as a sum of positive squares in 2 ways, for example, as 5608961449 + 5514250564 = 74893^2 + 74258^2 .

It is a cyclic number.

It is not a de Polignac number, because 11123212013 - 2⁶ = 11123211949 is a prime.

It is a super-2 number, since 2×11123212013² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 654306589 = 11123212013 / (1 + 1 + 1 + 2 + 3 + 2 + 1 + 2 + 0 + 1 + 3).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11123211982 and 11123212000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11123212019) 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, 327153278 + ... + 327153311.

It is an arithmetic number, because the mean of its divisors is an integer number (2944379655).

Almost surely, 2^11123212013 is an apocalyptic number.

It is an amenable number.

11123212013 is a deficient number, since it is larger than the sum of its proper divisors (654306607).

11123212013 is an equidigital number, since it uses as much as digits as its factorization.

11123212013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 654306606.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 11123212013 its reverse (31021232111), we get a palindrome (42144444124).

The spelling of 11123212013 in words is "eleven billion, one hundred twenty-three million, two hundred twelve thousand, thirteen".