51055550561 has 2 divisors, whose sum is σ = 51055550562. Its totient is φ = 51055550560.

The previous prime is 51055550551. The next prime is 51055550569. The reversal of 51055550561 is 16505555015.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48682009600 + 2373540961 = 220640^2 + 48719^2 .

It is a cyclic number.

It is not a de Polignac number, because 51055550561 - 2¹⁴ = 51055534177 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 (51055550569) 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, 25527775280 + 25527775281.

It is an arithmetic number, because the mean of its divisors is an integer number (25527775281).

Almost surely, 2^51055550561 is an apocalyptic number.

It is an amenable number.

51055550561 is a deficient number, since it is larger than the sum of its proper divisors (1).

51055550561 is an equidigital number, since it uses as much as digits as its factorization.

51055550561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 93750, while the sum is 38.

The spelling of 51055550561 in words is "fifty-one billion, fifty-five million, five hundred fifty thousand, five hundred sixty-one".