5181306661 has 2 divisors, whose sum is σ = 5181306662. Its totient is φ = 5181306660.

The previous prime is 5181306617. The next prime is 5181306671. The reversal of 5181306661 is 1666031815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5037450625 + 143856036 = 70975^2 + 11994^2 .

It is a cyclic number.

It is not a de Polignac number, because 5181306661 - 2⁹ = 5181306149 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 5181306661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5181306671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2590653330 + 2590653331.

It is an arithmetic number, because the mean of its divisors is an integer number (2590653331).

Almost surely, 2^5181306661 is an apocalyptic number.

It is an amenable number.

5181306661 is a deficient number, since it is larger than the sum of its proper divisors (1).

5181306661 is an equidigital number, since it uses as much as digits as its factorization.

5181306661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 5181306661 is about 71981.2938269381. The cubic root of 5181306661 is about 1730.3997050531.

The spelling of 5181306661 in words is "five billion, one hundred eighty-one million, three hundred six thousand, six hundred sixty-one".