78643807 has 16 divisors (see below), whose sum is σ = 89155584. Its totient is φ = 68724000.

The previous prime is 78643801. The next prime is 78643813. The reversal of 78643807 is 70834687.

It is an interprime number because it is at equal distance from previous prime (78643801) and next prime (78643813).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78643807 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78643801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56257 + ... + 57637.

It is an arithmetic number, because the mean of its divisors is an integer number (5572224).

Almost surely, 2^78643807 is an apocalyptic number.

78643807 is a deficient number, since it is larger than the sum of its proper divisors (10511777).

78643807 is a wasteful number, since it uses less digits than its factorization.

78643807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1590.

The product of its (nonzero) digits is 225792, while the sum is 43.

The square root of 78643807 is about 8868.1343584770. The cubic root of 78643807 is about 428.4381903333.

The spelling of 78643807 in words is "seventy-eight million, six hundred forty-three thousand, eight hundred seven".