51165125321 has 2 divisors, whose sum is σ = 51165125322. Its totient is φ = 51165125320.

The previous prime is 51165125317. The next prime is 51165125357. The reversal of 51165125321 is 12352156115.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29515240000 + 21649885321 = 171800^2 + 147139^2 .

It is a cyclic number.

It is not a de Polignac number, because 51165125321 - 2² = 51165125317 is a prime.

It is a super-2 number, since 2×51165125321² (a number of 22 digits) contains 22 as substring.

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 (51165124321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25582562660 + 25582562661.

It is an arithmetic number, because the mean of its divisors is an integer number (25582562661).

Almost surely, 2^51165125321 is an apocalyptic number.

It is an amenable number.

51165125321 is a deficient number, since it is larger than the sum of its proper divisors (1).

51165125321 is an equidigital number, since it uses as much as digits as its factorization.

51165125321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9000, while the sum is 32.

The spelling of 51165125321 in words is "fifty-one billion, one hundred sixty-five million, one hundred twenty-five thousand, three hundred twenty-one".