78789878 has 16 divisors (see below), whose sum is σ = 119684304. Its totient is φ = 38897760.

The previous prime is 78789877. The next prime is 78789901. The reversal of 78789878 is 87898787.

78789878 = 62² + 63² + ... + 618².

78789878 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 78789878.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78789877) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118868 + ... + 119528.

It is an arithmetic number, because the mean of its divisors is an integer number (7480269).

Almost surely, 2^78789878 is an apocalyptic number.

78789878 is a deficient number, since it is larger than the sum of its proper divisors (40894426).

78789878 is a wasteful number, since it uses less digits than its factorization.

78789878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1327.

The product of its digits is 12644352, while the sum is 62.

The square root of 78789878 is about 8876.3662610327. The cubic root of 78789878 is about 428.7032829956.

The spelling of 78789878 in words is "seventy-eight million, seven hundred eighty-nine thousand, eight hundred seventy-eight".