77317061891 has 2 divisors, whose sum is σ = 77317061892. Its totient is φ = 77317061890.

The previous prime is 77317061881. The next prime is 77317061897. The reversal of 77317061891 is 19816071377.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 77317061891 - 2⁶ = 77317061827 is a prime.

It is not a weakly prime, because it can be changed into another prime (77317061897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38658530945 + 38658530946.

It is an arithmetic number, because the mean of its divisors is an integer number (38658530946).

Almost surely, 2^77317061891 is an apocalyptic number.

77317061891 is a deficient number, since it is larger than the sum of its proper divisors (1).

77317061891 is an equidigital number, since it uses as much as digits as its factorization.

77317061891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 444528, while the sum is 50.

The spelling of 77317061891 in words is "seventy-seven billion, three hundred seventeen million, sixty-one thousand, eight hundred ninety-one".