78845281771 has 2 divisors, whose sum is σ = 78845281772. Its totient is φ = 78845281770.

The previous prime is 78845281741. The next prime is 78845281807. The reversal of 78845281771 is 17718254887.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78845281771 - 2⁹ = 78845281259 is a prime.

It is not a weakly prime, because it can be changed into another prime (78845281741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39422640885 + 39422640886.

It is an arithmetic number, because the mean of its divisors is an integer number (39422640886).

Almost surely, 2^78845281771 is an apocalyptic number.

78845281771 is a deficient number, since it is larger than the sum of its proper divisors (1).

78845281771 is an equidigital number, since it uses as much as digits as its factorization.

78845281771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7024640, while the sum is 58.

The spelling of 78845281771 in words is "seventy-eight billion, eight hundred forty-five million, two hundred eighty-one thousand, seven hundred seventy-one".