51931136513 has 2 divisors, whose sum is σ = 51931136514. Its totient is φ = 51931136512.

The previous prime is 51931136501. The next prime is 51931136519. The reversal of 51931136513 is 31563113915.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40205062144 + 11726074369 = 200512^2 + 108287^2 .

It is a cyclic number.

It is not a de Polignac number, because 51931136513 - 2⁶ = 51931136449 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 (51931136519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25965568256 + 25965568257.

It is an arithmetic number, because the mean of its divisors is an integer number (25965568257).

Almost surely, 2^51931136513 is an apocalyptic number.

It is an amenable number.

51931136513 is a deficient number, since it is larger than the sum of its proper divisors (1).

51931136513 is an equidigital number, since it uses as much as digits as its factorization.

51931136513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36450, while the sum is 38.

The spelling of 51931136513 in words is "fifty-one billion, nine hundred thirty-one million, one hundred thirty-six thousand, five hundred thirteen".