12891878 has 4 divisors (see below), whose sum is σ = 19337820. Its totient is φ = 6445938.

The previous prime is 12891871. The next prime is 12891881. The reversal of 12891878 is 87819821.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12891871) 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 as a sum of consecutive naturals, namely, 3222968 + ... + 3222971.

It is an arithmetic number, because the mean of its divisors is an integer number (4834455).

Almost surely, 2^12891878 is an apocalyptic number.

12891878 is a deficient number, since it is larger than the sum of its proper divisors (6445942).

12891878 is an equidigital number, since it uses as much as digits as its factorization.

12891878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6445941.

The product of its digits is 64512, while the sum is 44.

The square root of 12891878 is about 3590.5261452885. The cubic root of 12891878 is about 234.4797787629.

The spelling of 12891878 in words is "twelve million, eight hundred ninety-one thousand, eight hundred seventy-eight".