677729561 has 2 divisors, whose sum is σ = 677729562. Its totient is φ = 677729560.

The previous prime is 677729557. The next prime is 677729609. The reversal of 677729561 is 165927776.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 635997961 + 41731600 = 25219^2 + 6460^2 .

It is a cyclic number.

It is not a de Polignac number, because 677729561 - 2² = 677729557 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 (677729551) 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, 338864780 + 338864781.

It is an arithmetic number, because the mean of its divisors is an integer number (338864781).

Almost surely, 2^677729561 is an apocalyptic number.

It is an amenable number.

677729561 is a deficient number, since it is larger than the sum of its proper divisors (1).

677729561 is an equidigital number, since it uses as much as digits as its factorization.

677729561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1111320, while the sum is 50.

The square root of 677729561 is about 26033.2395410176. The cubic root of 677729561 is about 878.3861437841.

The spelling of 677729561 in words is "six hundred seventy-seven million, seven hundred twenty-nine thousand, five hundred sixty-one".