51510218069 has 2 divisors, whose sum is σ = 51510218070. Its totient is φ = 51510218068.

The previous prime is 51510218063. The next prime is 51510218099. The reversal of 51510218069 is 96081201515.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34498233169 + 17011984900 = 185737^2 + 130430^2 .

It is a cyclic number.

It is not a de Polignac number, because 51510218069 - 2¹² = 51510213973 is a prime.

It is a super-2 number, since 2×51510218069² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51510218063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25755109034 + 25755109035.

It is an arithmetic number, because the mean of its divisors is an integer number (25755109035).

Almost surely, 2^51510218069 is an apocalyptic number.

It is an amenable number.

51510218069 is a deficient number, since it is larger than the sum of its proper divisors (1).

51510218069 is an equidigital number, since it uses as much as digits as its factorization.

51510218069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 38.

The spelling of 51510218069 in words is "fifty-one billion, five hundred ten million, two hundred eighteen thousand, sixty-nine".