77668 has 6 divisors (see below), whose sum is σ = 135926. Its totient is φ = 38832.

The previous prime is 77659. The next prime is 77681. The reversal of 77668 is 86677.

It can be written as a sum of positive squares in only one way, i.e., 40804 + 36864 = 202^2 + 192^2 .

It is a zygodrome in base 5.

It is an unprimeable number.

77668 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9705 + ... + 9712.

2⁷⁷⁶⁶⁸ is an apocalyptic number.

It is an amenable number.

77668 is a deficient number, since it is larger than the sum of its proper divisors (58258).

77668 is a wasteful number, since it uses less digits than its factorization.

77668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19421 (or 19419 counting only the distinct ones).

The product of its digits is 14112, while the sum is 34.

The square root of 77668 is about 278.6897917040. The cubic root of 77668 is about 42.6658799768.

Subtracting 77668 from its reverse (86677), we obtain a palindrome (9009).

It can be divided in two parts, 7766 and 8, that multiplied together give a triangular number (62128 = T₃₅₂).

The spelling of 77668 in words is "seventy-seven thousand, six hundred sixty-eight".