78818885 has 16 divisors (see below), whose sum is σ = 101148912. Its totient is φ = 58752000.

The previous prime is 78818869. The next prime is 78818921. The reversal of 78818885 is 58881887.

It is a Cunningham number, because it is equal to 8878²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 14546596 + 64272289 = 3814^2 + 8017^2 .

It is not a de Polignac number, because 78818885 - 2⁴ = 78818869 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 3995 + ... + 13175.

It is an arithmetic number, because the mean of its divisors is an integer number (6321807).

Almost surely, 2^78818885 is an apocalyptic number.

It is an amenable number.

78818885 is a deficient number, since it is larger than the sum of its proper divisors (22330027).

78818885 is a wasteful number, since it uses less digits than its factorization.

78818885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9304.

The product of its digits is 1146880, while the sum is 53.

The square root of 78818885 is about 8878.0000563190. Note that the first 4 decimals coincide. The cubic root of 78818885 is about 428.7558864971.

The spelling of 78818885 in words is "seventy-eight million, eight hundred eighteen thousand, eight hundred eighty-five".