68156833921565 has 8 divisors (see below), whose sum is σ = 83783034869688. Its totient is φ = 53195577694720.

The previous prime is 68156833921531. The next prime is 68156833921621. The reversal of 68156833921565 is 56512933865186.

It can be written as a sum of positive squares in 4 ways, for example, as 5731949434201 + 62424884487364 = 2394149^2 + 7900942^2 .

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

It is not a de Polignac number, because 68156833921565 - 2³⁴ = 68139654052381 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 68156833921495 and 68156833921504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 166236180092 + ... + 166236180501.

It is an arithmetic number, because the mean of its divisors is an integer number (10472879358711).

Almost surely, 2^{68156833921565} is an apocalyptic number.

It is an amenable number.

68156833921565 is a deficient number, since it is larger than the sum of its proper divisors (15626200948123).

68156833921565 is a wasteful number, since it uses less digits than its factorization.

68156833921565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332472360639.

The product of its digits is 279936000, while the sum is 68.

The spelling of 68156833921565 in words is "sixty-eight trillion, one hundred fifty-six billion, eight hundred thirty-three million, nine hundred twenty-one thousand, five hundred sixty-five".