78687 has 12 divisors (see below), whose sum is σ = 130000. Its totient is φ = 44928.

The previous prime is 78653. The next prime is 78691.

It is a happy number.

78687 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 78687 - 2⁶ = 78623 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78607) 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 in 11 ways as a sum of consecutive naturals, for example, 562 + ... + 687.

2⁷⁸⁶⁸⁷ is an apocalyptic number.

78687 is a deficient number, since it is larger than the sum of its proper divisors (51313).

78687 is a wasteful number, since it uses less digits than its factorization.

78687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1262 (or 1259 counting only the distinct ones).

The product of its digits is 18816, while the sum is 36.

The square root of 78687 is about 280.5120318275. The cubic root of 78687 is about 42.8516612037.

It can be divided in two parts, 7868 and 7, that added together give a triangular number (7875 = T₁₂₅).

The spelling of 78687 in words is "seventy-eight thousand, six hundred eighty-seven".