78443887 has 2 divisors, whose sum is σ = 78443888. Its totient is φ = 78443886.

The previous prime is 78443851. The next prime is 78443917. The reversal of 78443887 is 78834487.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (78834487) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78443887 - 2⁷ = 78443759 is a prime.

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 78443887.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78243887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39221943 + 39221944.

It is an arithmetic number, because the mean of its divisors is an integer number (39221944).

Almost surely, 2^78443887 is an apocalyptic number.

78443887 is a deficient number, since it is larger than the sum of its proper divisors (1).

78443887 is an equidigital number, since it uses as much as digits as its factorization.

78443887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1204224, while the sum is 49.

The square root of 78443887 is about 8856.8553674541. The cubic root of 78443887 is about 428.0748387925.

The spelling of 78443887 in words is "seventy-eight million, four hundred forty-three thousand, eight hundred eighty-seven".