51585258509 has 2 divisors, whose sum is σ = 51585258510. Its totient is φ = 51585258508.

The previous prime is 51585258499. The next prime is 51585258539. The reversal of 51585258509 is 90585258515.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51584402884 + 855625 = 227122^2 + 925^2 .

It is a cyclic number.

It is not a de Polignac number, because 51585258509 - 2²⁰ = 51584209933 is a prime.

It is a super-2 number, since 2×51585258509² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51585258539) 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, 25792629254 + 25792629255.

It is an arithmetic number, because the mean of its divisors is an integer number (25792629255).

Almost surely, 2^51585258509 is an apocalyptic number.

It is an amenable number.

51585258509 is a deficient number, since it is larger than the sum of its proper divisors (1).

51585258509 is an equidigital number, since it uses as much as digits as its factorization.

51585258509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3600000, while the sum is 53.

The spelling of 51585258509 in words is "fifty-one billion, five hundred eighty-five million, two hundred fifty-eight thousand, five hundred nine".