51817208789 has 2 divisors, whose sum is σ = 51817208790. Its totient is φ = 51817208788.

The previous prime is 51817208777. The next prime is 51817208797. The reversal of 51817208789 is 98780271815.

51817208789 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., 37390796689 + 14426412100 = 193367^2 + 120110^2 .

It is a cyclic number.

It is not a de Polignac number, because 51817208789 - 2⁸ = 51817208533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51817207789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25908604394 + 25908604395.

It is an arithmetic number, because the mean of its divisors is an integer number (25908604395).

Almost surely, 2^51817208789 is an apocalyptic number.

It is an amenable number.

51817208789 is a deficient number, since it is larger than the sum of its proper divisors (1).

51817208789 is an equidigital number, since it uses as much as digits as its factorization.

51817208789 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2257920, while the sum is 56.

The spelling of 51817208789 in words is "fifty-one billion, eight hundred seventeen million, two hundred eight thousand, seven hundred eighty-nine".