78809243 has 2 divisors, whose sum is σ = 78809244. Its totient is φ = 78809242.

The previous prime is 78809209. The next prime is 78809249. The reversal of 78809243 is 34290887.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78809243 - 2¹⁸ = 78547099 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78809243.

It is not a weakly prime, because it can be changed into another prime (78809249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39404621 + 39404622.

It is an arithmetic number, because the mean of its divisors is an integer number (39404622).

Almost surely, 2^78809243 is an apocalyptic number.

78809243 is a deficient number, since it is larger than the sum of its proper divisors (1).

78809243 is an equidigital number, since it uses as much as digits as its factorization.

78809243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 78809243 is about 8877.4570120052. The cubic root of 78809243 is about 428.7384023926.

The spelling of 78809243 in words is "seventy-eight million, eight hundred nine thousand, two hundred forty-three".