51500535509 has 2 divisors, whose sum is σ = 51500535510. Its totient is φ = 51500535508.

The previous prime is 51500535439. The next prime is 51500535517. The reversal of 51500535509 is 90553500515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 48889632100 + 2610903409 = 221110^2 + 51097^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51500535509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51500535589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25750267754 + 25750267755.

It is an arithmetic number, because the mean of its divisors is an integer number (25750267755).

Almost surely, 2^51500535509 is an apocalyptic number.

It is an amenable number.

51500535509 is a deficient number, since it is larger than the sum of its proper divisors (1).

51500535509 is an equidigital number, since it uses as much as digits as its factorization.

51500535509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84375, while the sum is 38.

The spelling of 51500535509 in words is "fifty-one billion, five hundred million, five hundred thirty-five thousand, five hundred nine".