68312016181 has 4 divisors (see below), whose sum is σ = 72330370092. Its totient is φ = 64293662272.

The previous prime is 68312016173. The next prime is 68312016239. The reversal of 68312016181 is 18161021386.

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

It can be written as a sum of positive squares in 2 ways, for example, as 61301303281 + 7010712900 = 247591^2 + 83730^2 .

It is a cyclic number.

It is not a de Polignac number, because 68312016181 - 2³ = 68312016173 is a prime.

It is a super-2 number, since 2×68312016181² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 68312016181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68312016121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2009176930 + ... + 2009176963.

It is an arithmetic number, because the mean of its divisors is an integer number (18082592523).

Almost surely, 2^68312016181 is an apocalyptic number.

It is an amenable number.

68312016181 is a deficient number, since it is larger than the sum of its proper divisors (4018353911).

68312016181 is a wasteful number, since it uses less digits than its factorization.

68312016181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4018353910.

The product of its (nonzero) digits is 13824, while the sum is 37.

The spelling of 68312016181 in words is "sixty-eight billion, three hundred twelve million, sixteen thousand, one hundred eighty-one".