78645471847 has 2 divisors, whose sum is σ = 78645471848. Its totient is φ = 78645471846.

The previous prime is 78645471829. The next prime is 78645471929. The reversal of 78645471847 is 74817454687.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78645471847 - 2¹⁵ = 78645439079 is a prime.

It is a super-2 number, since 2×78645471847² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78645474847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39322735923 + 39322735924.

It is an arithmetic number, because the mean of its divisors is an integer number (39322735924).

Almost surely, 2^78645471847 is an apocalyptic number.

78645471847 is a deficient number, since it is larger than the sum of its proper divisors (1).

78645471847 is an equidigital number, since it uses as much as digits as its factorization.

78645471847 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42147840, while the sum is 61.

The spelling of 78645471847 in words is "seventy-eight billion, six hundred forty-five million, four hundred seventy-one thousand, eight hundred forty-seven".