68311554809 has 2 divisors, whose sum is σ = 68311554810. Its totient is φ = 68311554808.

The previous prime is 68311554793. The next prime is 68311554811. The reversal of 68311554809 is 90845511386.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58299551209 + 10012003600 = 241453^2 + 100060^2 .

It is a cyclic number.

It is not a de Polignac number, because 68311554809 - 2⁴ = 68311554793 is a prime.

It is a super-2 number, since 2×68311554809² (a number of 22 digits) contains 22 as substring.

Together with 68311554811, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (68311556809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34155777404 + 34155777405.

It is an arithmetic number, because the mean of its divisors is an integer number (34155777405).

Almost surely, 2^68311554809 is an apocalyptic number.

It is an amenable number.

68311554809 is a deficient number, since it is larger than the sum of its proper divisors (1).

68311554809 is an equidigital number, since it uses as much as digits as its factorization.

68311554809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1036800, while the sum is 50.

The spelling of 68311554809 in words is "sixty-eight billion, three hundred eleven million, five hundred fifty-four thousand, eight hundred nine".