78398071 has 2 divisors, whose sum is σ = 78398072. Its totient is φ = 78398070.

The previous prime is 78398069. The next prime is 78398087. The reversal of 78398071 is 17089387.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78398071 - 2¹ = 78398069 is a prime.

It is a super-2 number, since 2×78398071² = 12292515073042082, which contains 22 as substring.

Together with 78398069, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78398011) 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, 39199035 + 39199036.

It is an arithmetic number, because the mean of its divisors is an integer number (39199036).

Almost surely, 2^78398071 is an apocalyptic number.

78398071 is a deficient number, since it is larger than the sum of its proper divisors (1).

78398071 is an equidigital number, since it uses as much as digits as its factorization.

78398071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84672, while the sum is 43.

The square root of 78398071 is about 8854.2685186299. The cubic root of 78398071 is about 427.9914819832.

The spelling of 78398071 in words is "seventy-eight million, three hundred ninety-eight thousand, seventy-one".