78677 has 4 divisors (see below), whose sum is σ = 81420. Its totient is φ = 75936.

The previous prime is 78653. The next prime is 78691. The reversal of 78677 is 77687.

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 64516 + 14161 = 254^2 + 119^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78677 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 polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1328 + ... + 1385.

It is an arithmetic number, because the mean of its divisors is an integer number (20355).

2⁷⁸⁶⁷⁷ is an apocalyptic number.

It is an amenable number.

78677 is a deficient number, since it is larger than the sum of its proper divisors (2743).

78677 is a wasteful number, since it uses less digits than its factorization.

78677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2742.

The product of its digits is 16464, while the sum is 35.

The square root of 78677 is about 280.4942067138. The cubic root of 78677 is about 42.8498458476.

Subtracting from 78677 its reverse (77687), we obtain a triangular number (990 = T₄₄).

The spelling of 78677 in words is "seventy-eight thousand, six hundred seventy-seven".