1183987989 has 16 divisors (see below), whose sum is σ = 1754634240. Its totient is φ = 789065280.

The previous prime is 1183987969. The next prime is 1183988023. The reversal of 1183987989 is 9897893811.

It is not a de Polignac number, because 1183987989 - 2⁵ = 1183987957 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1183987939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 112044 + ... + 122154.

It is an arithmetic number, because the mean of its divisors is an integer number (109664640).

Almost surely, 2^1183987989 is an apocalyptic number.

It is an amenable number.

1183987989 is a deficient number, since it is larger than the sum of its proper divisors (570646251).

1183987989 is a wasteful number, since it uses less digits than its factorization.

1183987989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14457 (or 14451 counting only the distinct ones).

The product of its digits is 7838208, while the sum is 63.

The square root of 1183987989 is about 34409.1265364293. The cubic root of 1183987989 is about 1057.9109172151.

The spelling of 1183987989 in words is "one billion, one hundred eighty-three million, nine hundred eighty-seven thousand, nine hundred eighty-nine".