12165878 has 4 divisors (see below), whose sum is σ = 18248820. Its totient is φ = 6082938.

The previous prime is 12165869. The next prime is 12165893. The reversal of 12165878 is 87856121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87856121 = 2239 ⋅39239.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3041468 + ... + 3041471.

It is an arithmetic number, because the mean of its divisors is an integer number (4562205).

Almost surely, 2^12165878 is an apocalyptic number.

12165878 is a deficient number, since it is larger than the sum of its proper divisors (6082942).

12165878 is an equidigital number, since it uses as much as digits as its factorization.

12165878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6082941.

The product of its digits is 26880, while the sum is 38.

The square root of 12165878 is about 3487.9618690576. The cubic root of 12165878 is about 229.9929298394.

The spelling of 12165878 in words is "twelve million, one hundred sixty-five thousand, eight hundred seventy-eight".