68128434917856 has 384 divisors, whose sum is σ = 216492676646400. Its totient is φ = 20759902248960.

The previous prime is 68128434917849. The next prime is 68128434917857. The reversal of 68128434917856 is 65871943482186.

68128434917856 is a `hidden beast` number, since 6 + 8 + 1 + 2 + 84 + 3 + 491 + 7 + 8 + 56 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68128434917857) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 112752226 + ... + 113354846.

It is an arithmetic number, because the mean of its divisors is an integer number (563783012100).

Almost surely, 2^{68128434917856} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 68128434917856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108246338323200).

68128434917856 is an abundant number, since it is smaller than the sum of its proper divisors (148364241728544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

68128434917856 is a wasteful number, since it uses less digits than its factorization.

68128434917856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 602879 (or 602865 counting only the distinct ones).

The product of its digits is 557383680, while the sum is 72.

The spelling of 68128434917856 in words is "sixty-eight trillion, one hundred twenty-eight billion, four hundred thirty-four million, nine hundred seventeen thousand, eight hundred fifty-six".