78745 has 4 divisors (see below), whose sum is σ = 94500. Its totient is φ = 62992.

The previous prime is 78737. The next prime is 78779. The reversal of 78745 is 54787.

It is a happy number.

78745 is nontrivially palindromic in base 2.

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 11664 + 67081 = 108^2 + 259^2 .

It is a cyclic number.

It is not a de Polignac number, because 78745 - 2³ = 78737 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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

It is a plaindrome in base 16.

It is a zygodrome in base 3.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7870 + ... + 7879.

It is an arithmetic number, because the mean of its divisors is an integer number (23625).

2⁷⁸⁷⁴⁵ is an apocalyptic number.

It is an amenable number.

78745 is a deficient number, since it is larger than the sum of its proper divisors (15755).

78745 is a wasteful number, since it uses less digits than its factorization.

78745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15754.

The product of its digits is 7840, while the sum is 31.

The square root of 78745 is about 280.6153951586. The cubic root of 78745 is about 42.8621872369.

The spelling of 78745 in words is "seventy-eight thousand, seven hundred forty-five".