51186668549 has 2 divisors, whose sum is σ = 51186668550. Its totient is φ = 51186668548.

The previous prime is 51186668531. The next prime is 51186668557. The reversal of 51186668549 is 94586668115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34552117924 + 16634550625 = 185882^2 + 128975^2 .

It is a cyclic number.

It is not a de Polignac number, because 51186668549 - 2⁸ = 51186668293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51186668569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25593334274 + 25593334275.

It is an arithmetic number, because the mean of its divisors is an integer number (25593334275).

Almost surely, 2^51186668549 is an apocalyptic number.

It is an amenable number.

51186668549 is a deficient number, since it is larger than the sum of its proper divisors (1).

51186668549 is an equidigital number, since it uses as much as digits as its factorization.

51186668549 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12441600, while the sum is 59.

It can be divided in two parts, 5118666 and 8549, that added together give a palindrome (5127215).

The spelling of 51186668549 in words is "fifty-one billion, one hundred eighty-six million, six hundred sixty-eight thousand, five hundred forty-nine".