68731600081 has 4 divisors (see below), whose sum is σ = 70589210932. Its totient is φ = 66873989232.

The previous prime is 68731600073. The next prime is 68731600129. The reversal of 68731600081 is 18000613786.

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 32403240081 + 36328360000 = 180009^2 + 190600^2 .

It is a cyclic number.

It is not a de Polignac number, because 68731600081 - 2³ = 68731600073 is a prime.

It is a super-2 number, since 2×68731600081² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68731600031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 928805370 + ... + 928805443.

It is an arithmetic number, because the mean of its divisors is an integer number (17647302733).

Almost surely, 2^68731600081 is an apocalyptic number.

It is an amenable number.

68731600081 is a deficient number, since it is larger than the sum of its proper divisors (1857610851).

68731600081 is a wasteful number, since it uses less digits than its factorization.

68731600081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1857610850.

The product of its (nonzero) digits is 48384, while the sum is 40.

The spelling of 68731600081 in words is "sixty-eight billion, seven hundred thirty-one million, six hundred thousand, eighty-one".