68387888471809 has 27 divisors (see below), whose sum is σ = 70253618820163. Its totient is φ = 66571060850000.

The previous prime is 68387888471807. The next prime is 68387888471849. The reversal of 68387888471809 is 90817488878386.

The square root of 68387888471809 is 8269697.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 58980049943409 + 9407838528400 = 7679847^2 + 3067220^2 .

It is not a de Polignac number, because 68387888471809 - 2¹ = 68387888471807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68387888471807) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 97557615159 + ... + 97557615859.

Almost surely, 2^{68387888471809} is an apocalyptic number.

68387888471809 is the 8269697-th square number.

68387888471809 is the 4134849-th centered octagonal number.

It is an amenable number.

68387888471809 is a deficient number, since it is larger than the sum of its proper divisors (1865730348354).

68387888471809 is an frugal number, since it uses more digits than its factorization.

68387888471809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1998 (or 999 counting only the distinct ones).

The product of its (nonzero) digits is 8323596288, while the sum is 85.

The spelling of 68387888471809 in words is "sixty-eight trillion, three hundred eighty-seven billion, eight hundred eighty-eight million, four hundred seventy-one thousand, eight hundred nine".