77781113 has 2 divisors, whose sum is σ = 77781114. Its totient is φ = 77781112.

The previous prime is 77781107. The next prime is 77781149. The reversal of 77781113 is 31118777.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71690089 + 6091024 = 8467^2 + 2468^2 .

It is a cyclic number.

It is not a de Polignac number, because 77781113 - 2²⁴ = 61003897 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (77786113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38890556 + 38890557.

It is an arithmetic number, because the mean of its divisors is an integer number (38890557).

Almost surely, 2^77781113 is an apocalyptic number.

It is an amenable number.

77781113 is a deficient number, since it is larger than the sum of its proper divisors (1).

77781113 is an equidigital number, since it uses as much as digits as its factorization.

77781113 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8232, while the sum is 35.

The square root of 77781113 is about 8819.3601241813. The cubic root of 77781113 is about 426.8658230268.

The spelling of 77781113 in words is "seventy-seven million, seven hundred eighty-one thousand, one hundred thirteen".