68616537685 has 4 divisors (see below), whose sum is σ = 82339845228. Its totient is φ = 54893230144.

The previous prime is 68616537673. The next prime is 68616537709. The reversal of 68616537685 is 58673561686.

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 10904162929 + 57712374756 = 104423^2 + 240234^2 .

It is a cyclic number.

It is not a de Polignac number, because 68616537685 - 2³¹ = 66469054037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 6861653764 + ... + 6861653773.

It is an arithmetic number, because the mean of its divisors is an integer number (20584961307).

Almost surely, 2^68616537685 is an apocalyptic number.

It is an amenable number.

68616537685 is a deficient number, since it is larger than the sum of its proper divisors (13723307543).

68616537685 is a wasteful number, since it uses less digits than its factorization.

68616537685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13723307542.

The product of its digits is 43545600, while the sum is 61.

The spelling of 68616537685 in words is "sixty-eight billion, six hundred sixteen million, five hundred thirty-seven thousand, six hundred eighty-five".