77966765 has 4 divisors (see below), whose sum is σ = 93560124. Its totient is φ = 62373408.

The previous prime is 77966737. The next prime is 77966809. The reversal of 77966765 is 56766977.

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 36929929 + 41036836 = 6077^2 + 6406^2 .

It is a cyclic number.

It is not a de Polignac number, because 77966765 - 2²⁶ = 10857901 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 7796672 + ... + 7796681.

It is an arithmetic number, because the mean of its divisors is an integer number (23390031).

Almost surely, 2^77966765 is an apocalyptic number.

It is an amenable number.

77966765 is a deficient number, since it is larger than the sum of its proper divisors (15593359).

77966765 is a wasteful number, since it uses less digits than its factorization.

77966765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15593358.

The product of its digits is 3333960, while the sum is 53.

The square root of 77966765 is about 8829.8791044951. The cubic root of 77966765 is about 427.2051750140.

The spelling of 77966765 in words is "seventy-seven million, nine hundred sixty-six thousand, seven hundred sixty-five".