12731987 has 2 divisors, whose sum is σ = 12731988. Its totient is φ = 12731986.

The previous prime is 12731969. The next prime is 12731989. The reversal of 12731987 is 78913721.

It is a strong prime.

It is an emirp because it is prime and its reverse (78913721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12731987 - 2⁶ = 12731923 is a prime.

Together with 12731989, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12731987.

It is not a weakly prime, because it can be changed into another prime (12731989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6365993 + 6365994.

It is an arithmetic number, because the mean of its divisors is an integer number (6365994).

Almost surely, 2^12731987 is an apocalyptic number.

12731987 is a deficient number, since it is larger than the sum of its proper divisors (1).

12731987 is an equidigital number, since it uses as much as digits as its factorization.

12731987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21168, while the sum is 38.

The square root of 12731987 is about 3568.1909982511. The cubic root of 12731987 is about 233.5063680216.

The spelling of 12731987 in words is "twelve million, seven hundred thirty-one thousand, nine hundred eighty-seven".