77739307777 has 4 divisors (see below), whose sum is σ = 77739878916. Its totient is φ = 77738736640.

The previous prime is 77739307759. The next prime is 77739307799. The reversal of 77739307777 is 77770393777.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 77770393777 = 3917 ⋅19854581.

It can be written as a sum of positive squares in 2 ways, for example, as 29780059761 + 47959248016 = 172569^2 + 218996^2 .

It is a cyclic number.

It is not a de Polignac number, because 77739307777 - 2³¹ = 75591824129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77739307277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50193 + ... + 397489.

It is an arithmetic number, because the mean of its divisors is an integer number (19434969729).

Almost surely, 2^77739307777 is an apocalyptic number.

It is an amenable number.

77739307777 is a deficient number, since it is larger than the sum of its proper divisors (571139).

77739307777 is a wasteful number, since it uses less digits than its factorization.

77739307777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 571138.

The product of its (nonzero) digits is 66706983, while the sum is 64.

The spelling of 77739307777 in words is "seventy-seven billion, seven hundred thirty-nine million, three hundred seven thousand, seven hundred seventy-seven".