77768771 has 4 divisors (see below), whose sum is σ = 78171912. Its totient is φ = 77365632.

The previous prime is 77768741. The next prime is 77768809. The reversal of 77768771 is 17786777.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77768771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77768701) 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, 201281 + ... + 201666.

It is an arithmetic number, because the mean of its divisors is an integer number (19542978).

Almost surely, 2^77768771 is an apocalyptic number.

77768771 is a deficient number, since it is larger than the sum of its proper divisors (403141).

77768771 is a wasteful number, since it uses less digits than its factorization.

77768771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403140.

The product of its digits is 806736, while the sum is 50.

The square root of 77768771 is about 8818.6603857956. The cubic root of 77768771 is about 426.8432440379.

The spelling of 77768771 in words is "seventy-seven million, seven hundred sixty-eight thousand, seven hundred seventy-one".