12719891 has 2 divisors, whose sum is σ = 12719892. Its totient is φ = 12719890.

The previous prime is 12719887. The next prime is 12719929. The reversal of 12719891 is 19891721.

It is an a-pointer prime, because the next prime (12719929) can be obtained adding 12719891 to its sum of digits (38).

It is a weak prime.

It is an emirp because it is prime and its reverse (19891721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12719891 - 2² = 12719887 is a prime.

It is not a weakly prime, because it can be changed into another prime (12719821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6359945 + 6359946.

It is an arithmetic number, because the mean of its divisors is an integer number (6359946).

Almost surely, 2^12719891 is an apocalyptic number.

12719891 is a deficient number, since it is larger than the sum of its proper divisors (1).

12719891 is an equidigital number, since it uses as much as digits as its factorization.

12719891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9072, while the sum is 38.

The square root of 12719891 is about 3566.4956189515. The cubic root of 12719891 is about 233.4323971646.

The spelling of 12719891 in words is "twelve million, seven hundred nineteen thousand, eight hundred ninety-one".