78681745 has 4 divisors (see below), whose sum is σ = 94418100. Its totient is φ = 62945392.

The previous prime is 78681737. The next prime is 78681761. The reversal of 78681745 is 54718687.

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

It can be written as a sum of positive squares in 2 ways, for example, as 32672656 + 46009089 = 5716^2 + 6783^2 .

It is a cyclic number.

It is not a de Polignac number, because 78681745 - 2³ = 78681737 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78681695 and 78681704.

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 in 3 ways as a sum of consecutive naturals, for example, 7868170 + ... + 7868179.

It is an arithmetic number, because the mean of its divisors is an integer number (23604525).

Almost surely, 2^78681745 is an apocalyptic number.

It is an amenable number.

78681745 is a deficient number, since it is larger than the sum of its proper divisors (15736355).

78681745 is a wasteful number, since it uses less digits than its factorization.

78681745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15736354.

The product of its digits is 376320, while the sum is 46.

The square root of 78681745 is about 8870.2731074077. The cubic root of 78681745 is about 428.5070725323.

The spelling of 78681745 in words is "seventy-eight million, six hundred eighty-one thousand, seven hundred forty-five".