1200111111 has 6 divisors (see below), whose sum is σ = 1733493840. Its totient is φ = 800074068.

The previous prime is 1200111061. The next prime is 1200111119. The reversal of 1200111111 is 1111110021.

It is a de Polignac number, because none of the positive numbers 2^k-1200111111 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 133345679 = 1200111111 / (1 + 2 + 0 + 0 + 1 + 1 + 1 + 1 + 1 + 1).

1200111111 is a modest number, since divided by 111111 gives 1200 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 1200111093 and 1200111102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200111119) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 66672831 + ... + 66672848.

It is an arithmetic number, because the mean of its divisors is an integer number (288915640).

Almost surely, 2^1200111111 is an apocalyptic number.

1200111111 is a deficient number, since it is larger than the sum of its proper divisors (533382729).

1200111111 is a wasteful number, since it uses less digits than its factorization.

1200111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133345685 (or 133345682 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

The square root of 1200111111 is about 34642.6198633995. The cubic root of 1200111111 is about 1062.6913662416.

Adding to 1200111111 its reverse (1111110021), we get a palindrome (2311221132).

The spelling of 1200111111 in words is "one billion, two hundred million, one hundred eleven thousand, one hundred eleven".