78891143 has 2 divisors, whose sum is σ = 78891144. Its totient is φ = 78891142.

The previous prime is 78891119. The next prime is 78891149. The reversal of 78891143 is 34119887.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78891143 - 2¹⁸ = 78628999 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78891143.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78891149) 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, 39445571 + 39445572.

It is an arithmetic number, because the mean of its divisors is an integer number (39445572).

Almost surely, 2^78891143 is an apocalyptic number.

78891143 is a deficient number, since it is larger than the sum of its proper divisors (1).

78891143 is an equidigital number, since it uses as much as digits as its factorization.

78891143 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 41.

The square root of 78891143 is about 8882.0686216669. The cubic root of 78891143 is about 428.8868685592.

The spelling of 78891143 in words is "seventy-eight million, eight hundred ninety-one thousand, one hundred forty-three".