68131135491 has 8 divisors (see below), whose sum is σ = 91081202880. Its totient is φ = 45300912552.

The previous prime is 68131135477. The next prime is 68131135493. The reversal of 68131135491 is 19453113186.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 68131135491 - 2⁵ = 68131135459 is a prime.

It is a super-2 number, since 2×68131135491² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (68131135493) 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 7 ways as a sum of consecutive naturals, for example, 29959785 + ... + 29962058.

It is an arithmetic number, because the mean of its divisors is an integer number (11385150360).

Almost surely, 2^68131135491 is an apocalyptic number.

68131135491 is a deficient number, since it is larger than the sum of its proper divisors (22950067389).

68131135491 is a wasteful number, since it uses less digits than its factorization.

68131135491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59922225.

The product of its digits is 77760, while the sum is 42.

The spelling of 68131135491 in words is "sixty-eight billion, one hundred thirty-one million, one hundred thirty-five thousand, four hundred ninety-one".