1243112111 has 4 divisors (see below), whose sum is σ = 1243946232. Its totient is φ = 1242277992.

The previous prime is 1243112099. The next prime is 1243112137. The reversal of 1243112111 is 1112113421.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1243112111 - 2¹⁴ = 1243095727 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1243112111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243112161) 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, 414821 + ... + 417806.

It is an arithmetic number, because the mean of its divisors is an integer number (310986558).

Almost surely, 2^1243112111 is an apocalyptic number.

1243112111 is a deficient number, since it is larger than the sum of its proper divisors (834121).

1243112111 is an equidigital number, since it uses as much as digits as its factorization.

1243112111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 834120.

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

The square root of 1243112111 is about 35257.7950388279. The cubic root of 1243112111 is about 1075.2350986802.

Adding to 1243112111 its reverse (1112113421), we get a palindrome (2355225532).

It can be divided in two parts, 12431 and 12111, that added together give a palindrome (24542).

The spelling of 1243112111 in words is "one billion, two hundred forty-three million, one hundred twelve thousand, one hundred eleven".