12138109965 has 12 divisors (see below), whose sum is σ = 21039390684. Its totient is φ = 6473658624.

The previous prime is 12138109957. The next prime is 12138110009. The reversal of 12138109965 is 56990183121.

12138109965 is a `hidden beast` number, since 121 + 381 + 0 + 99 + 65 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7283086281 + 4855023684 = 85341^2 + 69678^2 .

It is not a de Polignac number, because 12138109965 - 2³ = 12138109957 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 269735777 = 12138109965 / (1 + 2 + 1 + 3 + 8 + 1 + 0 + 9 + 9 + 6 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 12138109965.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 134867844 + ... + 134867933.

It is an arithmetic number, because the mean of its divisors is an integer number (1753282557).

Almost surely, 2^12138109965 is an apocalyptic number.

12138109965 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12138109965 is a deficient number, since it is larger than the sum of its proper divisors (8901280719).

12138109965 is a wasteful number, since it uses less digits than its factorization.

12138109965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269735788 (or 269735785 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 45.

The spelling of 12138109965 in words is "twelve billion, one hundred thirty-eight million, one hundred nine thousand, nine hundred sixty-five".