51731993 has 2 divisors, whose sum is σ = 51731994. Its totient is φ = 51731992.

The previous prime is 51731941. The next prime is 51732001. The reversal of 51731993 is 39913715.

51731993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 41822089 + 9909904 = 6467^2 + 3148^2 .

It is a cyclic number.

It is not a de Polignac number, because 51731993 - 2⁶ = 51731929 is a prime.

It is not a weakly prime, because it can be changed into another prime (51731903) by changing a digit.

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

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25865996 + 25865997.

It is an arithmetic number, because the mean of its divisors is an integer number (25865997).

Almost surely, 2^51731993 is an apocalyptic number.

It is an amenable number.

51731993 is a deficient number, since it is larger than the sum of its proper divisors (1).

51731993 is an equidigital number, since it uses as much as digits as its factorization.

51731993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25515, while the sum is 38.

The square root of 51731993 is about 7192.4956030574. The cubic root of 51731993 is about 372.6087678410.

The spelling of 51731993 in words is "fifty-one million, seven hundred thirty-one thousand, nine hundred ninety-three".