12987871 has 4 divisors (see below), whose sum is σ = 13986952. Its totient is φ = 11988792.

The previous prime is 12987869. The next prime is 12987889. The reversal of 12987871 is 17878921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17878921 = 349 ⋅51229.

It is a cyclic number.

It is not a de Polignac number, because 12987871 - 2¹ = 12987869 is a prime.

It is a super-2 number, since 2×12987871² = 337369586225282, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12987841) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 499521 + ... + 499546.

It is an arithmetic number, because the mean of its divisors is an integer number (3496738).

Almost surely, 2^12987871 is an apocalyptic number.

12987871 is a deficient number, since it is larger than the sum of its proper divisors (999081).

12987871 is an equidigital number, since it uses as much as digits as its factorization.

12987871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 999080.

The product of its digits is 56448, while the sum is 43.

The square root of 12987871 is about 3603.8688932868. The cubic root of 12987871 is about 235.0603195091.

The spelling of 12987871 in words is "twelve million, nine hundred eighty-seven thousand, eight hundred seventy-one".