78680978 has 4 divisors (see below), whose sum is σ = 118021470. Its totient is φ = 39340488.

The previous prime is 78680977. The next prime is 78680983. The reversal of 78680978 is 87908687.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 68840209 + 9840769 = 8297^2 + 3137^2 .

It is not an unprimeable number, because it can be changed into a prime (78680971) 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 as a sum of consecutive naturals, namely, 19670243 + ... + 19670246.

Almost surely, 2^78680978 is an apocalyptic number.

78680978 is a deficient number, since it is larger than the sum of its proper divisors (39340492).

78680978 is a wasteful number, since it uses less digits than its factorization.

78680978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39340491.

The product of its (nonzero) digits is 1354752, while the sum is 53.

The square root of 78680978 is about 8870.2298730078. The cubic root of 78680978 is about 428.5056801467.

The spelling of 78680978 in words is "seventy-eight million, six hundred eighty thousand, nine hundred seventy-eight".