78739 has 4 divisors (see below), whose sum is σ = 79920. Its totient is φ = 77560.

The previous prime is 78737. The next prime is 78779. The reversal of 78739 is 93787.

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

It is a cyclic number.

It is not a de Polignac number, because 78739 - 2¹ = 78737 is a prime.

It is a Duffinian number.

78739 is a lucky number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (78737) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 484 + ... + 625.

It is an arithmetic number, because the mean of its divisors is an integer number (19980).

2⁷⁸⁷³⁹ is an apocalyptic number.

78739 is a deficient number, since it is larger than the sum of its proper divisors (1181).

78739 is a wasteful number, since it uses less digits than its factorization.

78739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1180.

The product of its digits is 10584, while the sum is 34.

The square root of 78739 is about 280.6047041658. The cubic root of 78739 is about 42.8610985767.

The spelling of 78739 in words is "seventy-eight thousand, seven hundred thirty-nine".