78554777017 has 2 divisors, whose sum is σ = 78554777018. Its totient is φ = 78554777016.

The previous prime is 78554776999. The next prime is 78554777099. The reversal of 78554777017 is 71077745587.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40328270761 + 38226506256 = 200819^2 + 195516^2 .

It is a cyclic number.

It is not a de Polignac number, because 78554777017 - 2²⁷ = 78420559289 is a prime.

It is not a weakly prime, because it can be changed into another prime (78554777417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39277388508 + 39277388509.

It is an arithmetic number, because the mean of its divisors is an integer number (39277388509).

Almost surely, 2^78554777017 is an apocalyptic number.

It is an amenable number.

78554777017 is a deficient number, since it is larger than the sum of its proper divisors (1).

78554777017 is an equidigital number, since it uses as much as digits as its factorization.

78554777017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13445600, while the sum is 58.

The spelling of 78554777017 in words is "seventy-eight billion, five hundred fifty-four million, seven hundred seventy-seven thousand, seventeen".