51756260921 has 2 divisors, whose sum is σ = 51756260922. Its totient is φ = 51756260920.

The previous prime is 51756260909. The next prime is 51756260923. The reversal of 51756260921 is 12906265715.

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., 32647069225 + 19109191696 = 180685^2 + 138236^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51756260921 is a prime.

It is a Sophie Germain prime.

Together with 51756260923, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (51756260923) 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, 25878130460 + 25878130461.

It is an arithmetic number, because the mean of its divisors is an integer number (25878130461).

Almost surely, 2^51756260921 is an apocalyptic number.

It is an amenable number.

51756260921 is a deficient number, since it is larger than the sum of its proper divisors (1).

51756260921 is an equidigital number, since it uses as much as digits as its factorization.

51756260921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 226800, while the sum is 44.

The spelling of 51756260921 in words is "fifty-one billion, seven hundred fifty-six million, two hundred sixty thousand, nine hundred twenty-one".