1185665811 has 12 divisors (see below), whose sum is σ = 1737670536. Its totient is φ = 718585120.

The previous prime is 1185665791. The next prime is 1185665827.

1185665811 is nontrivially palindromic in base 10.

1185665811 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1185665811 - 2¹⁰ = 1185664787 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1185660811) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1632786 + ... + 1633511.

It is an arithmetic number, because the mean of its divisors is an integer number (144805878).

Almost surely, 2^1185665811 is an apocalyptic number.

1185665811 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1185665811 is a deficient number, since it is larger than the sum of its proper divisors (552004725).

1185665811 is a wasteful number, since it uses less digits than its factorization.

1185665811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3266322 (or 3266311 counting only the distinct ones).

The product of its digits is 57600, while the sum is 42.

The square root of 1185665811 is about 34433.4983845673. The cubic root of 1185665811 is about 1058.4104010067.

The spelling of 1185665811 in words is "one billion, one hundred eighty-five million, six hundred sixty-five thousand, eight hundred eleven".