51121655317 has 2 divisors, whose sum is σ = 51121655318. Its totient is φ = 51121655316.

The previous prime is 51121655257. The next prime is 51121655393. The reversal of 51121655317 is 71355612115.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49208992561 + 1912662756 = 221831^2 + 43734^2 .

It is a cyclic number.

It is not a de Polignac number, because 51121655317 - 2¹¹ = 51121653269 is a prime.

It is a super-2 number, since 2×51121655317² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51121655017) 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, 25560827658 + 25560827659.

It is an arithmetic number, because the mean of its divisors is an integer number (25560827659).

Almost surely, 2^51121655317 is an apocalyptic number.

It is an amenable number.

51121655317 is a deficient number, since it is larger than the sum of its proper divisors (1).

51121655317 is an equidigital number, since it uses as much as digits as its factorization.

51121655317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31500, while the sum is 37.

The spelling of 51121655317 in words is "fifty-one billion, one hundred twenty-one million, six hundred fifty-five thousand, three hundred seventeen".