78319847 has 2 divisors, whose sum is σ = 78319848. Its totient is φ = 78319846.

The previous prime is 78319823. The next prime is 78319883. The reversal of 78319847 is 74891387.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78319847 - 2⁶ = 78319783 is a prime.

It is a super-2 number, since 2×78319847² = 12267996868206818, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78319147) 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, 39159923 + 39159924.

It is an arithmetic number, because the mean of its divisors is an integer number (39159924).

Almost surely, 2^78319847 is an apocalyptic number.

78319847 is a deficient number, since it is larger than the sum of its proper divisors (1).

78319847 is an equidigital number, since it uses as much as digits as its factorization.

78319847 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 47.

The square root of 78319847 is about 8849.8501117251. The cubic root of 78319847 is about 427.8490875493.

The spelling of 78319847 in words is "seventy-eight million, three hundred nineteen thousand, eight hundred forty-seven".