51021847081 has 2 divisors, whose sum is σ = 51021847082. Its totient is φ = 51021847080.

The previous prime is 51021847061. The next prime is 51021847111. The reversal of 51021847081 is 18074812015.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27935779600 + 23086067481 = 167140^2 + 151941^2 .

It is a cyclic number.

It is not a de Polignac number, because 51021847081 - 2³⁵ = 16662108713 is a prime.

It is a super-2 number, since 2×51021847081² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51021847081.

It is not a weakly prime, because it can be changed into another prime (51021847001) 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, 25510923540 + 25510923541.

It is an arithmetic number, because the mean of its divisors is an integer number (25510923541).

Almost surely, 2^51021847081 is an apocalyptic number.

It is an amenable number.

51021847081 is a deficient number, since it is larger than the sum of its proper divisors (1).

51021847081 is an equidigital number, since it uses as much as digits as its factorization.

51021847081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17920, while the sum is 37.

The spelling of 51021847081 in words is "fifty-one billion, twenty-one million, eight hundred forty-seven thousand, eighty-one".