68387881511 has 4 divisors (see below), whose sum is σ = 69678218952. Its totient is φ = 67097544072.

The previous prime is 68387881501. The next prime is 68387881531. The reversal of 68387881511 is 11518878386.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 68387881511 - 2⁶ = 68387881447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68387881501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 645168641 + ... + 645168746.

It is an arithmetic number, because the mean of its divisors is an integer number (17419554738).

Almost surely, 2^68387881511 is an apocalyptic number.

68387881511 is a deficient number, since it is larger than the sum of its proper divisors (1290337441).

68387881511 is a wasteful number, since it uses less digits than its factorization.

68387881511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1290337440.

The product of its digits is 2580480, while the sum is 56.

The spelling of 68387881511 in words is "sixty-eight billion, three hundred eighty-seven million, eight hundred eighty-one thousand, five hundred eleven".