77814368257 has 2 divisors, whose sum is σ = 77814368258. Its totient is φ = 77814368256.

The previous prime is 77814368173. The next prime is 77814368299. The reversal of 77814368257 is 75286341877.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50115090496 + 27699277761 = 223864^2 + 166431^2 .

It is a cyclic number.

It is not a de Polignac number, because 77814368257 - 2¹¹ = 77814366209 is a prime.

It is not a weakly prime, because it can be changed into another prime (77814368557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38907184128 + 38907184129.

It is an arithmetic number, because the mean of its divisors is an integer number (38907184129).

Almost surely, 2^77814368257 is an apocalyptic number.

It is an amenable number.

77814368257 is a deficient number, since it is larger than the sum of its proper divisors (1).

77814368257 is an equidigital number, since it uses as much as digits as its factorization.

77814368257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15805440, while the sum is 58.

It can be divided in two parts, 778143 and 68257, that added together give a square (846400 = 920²).

The spelling of 77814368257 in words is "seventy-seven billion, eight hundred fourteen million, three hundred sixty-eight thousand, two hundred fifty-seven".