78731843 has 2 divisors, whose sum is σ = 78731844. Its totient is φ = 78731842.

The previous prime is 78731837. The next prime is 78731867. The reversal of 78731843 is 34813787.

It is a weak prime.

It is an emirp because it is prime and its reverse (34813787) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78731843 - 2²² = 74537539 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78731843.

It is not a weakly prime, because it can be changed into another prime (78731813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39365921 + 39365922.

It is an arithmetic number, because the mean of its divisors is an integer number (39365922).

Almost surely, 2^78731843 is an apocalyptic number.

78731843 is a deficient number, since it is larger than the sum of its proper divisors (1).

78731843 is an equidigital number, since it uses as much as digits as its factorization.

78731843 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112896, while the sum is 41.

The square root of 78731843 is about 8873.0965846203. The cubic root of 78731843 is about 428.5979991410.

The spelling of 78731843 in words is "seventy-eight million, seven hundred thirty-one thousand, eight hundred forty-three".