78908686 has 4 divisors (see below), whose sum is σ = 118363032. Its totient is φ = 39454342.

The previous prime is 78908663. The next prime is 78908701. The reversal of 78908686 is 68680987.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 68680987 = 283 ⋅242689.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 19727170 + ... + 19727173.

It is an arithmetic number, because the mean of its divisors is an integer number (29590758).

Almost surely, 2^78908686 is an apocalyptic number.

78908686 is a deficient number, since it is larger than the sum of its proper divisors (39454346).

78908686 is a wasteful number, since it uses less digits than its factorization.

78908686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39454345.

The product of its (nonzero) digits is 1161216, while the sum is 52.

The square root of 78908686 is about 8883.0561182512. The cubic root of 78908686 is about 428.9186566848.

The spelling of 78908686 in words is "seventy-eight million, nine hundred eight thousand, six hundred eighty-six".