68557350509 has 2 divisors, whose sum is σ = 68557350510. Its totient is φ = 68557350508.

The previous prime is 68557350481. The next prime is 68557350607. The reversal of 68557350509 is 90505375586.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48916168900 + 19641181609 = 221170^2 + 140147^2 .

It is a cyclic number.

It is not a de Polignac number, because 68557350509 - 2¹² = 68557346413 is a prime.

It is a super-2 number, since 2×68557350509² (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 (68557350409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34278675254 + 34278675255.

It is an arithmetic number, because the mean of its divisors is an integer number (34278675255).

Almost surely, 2^68557350509 is an apocalyptic number.

It is an amenable number.

68557350509 is a deficient number, since it is larger than the sum of its proper divisors (1).

68557350509 is an equidigital number, since it uses as much as digits as its factorization.

68557350509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5670000, while the sum is 53.

The spelling of 68557350509 in words is "sixty-eight billion, five hundred fifty-seven million, three hundred fifty thousand, five hundred nine".