681728256 has 216 divisors, whose sum is σ = 2205263424. Its totient is φ = 200724480.

The previous prime is 681728233. The next prime is 681728261. The reversal of 681728256 is 652827186.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 937365 + ... + 938091.

Almost surely, 2^681728256 is an apocalyptic number.

681728256 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 681728256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1102631712).

681728256 is an abundant number, since it is smaller than the sum of its proper divisors (1523535168).

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

681728256 is a wasteful number, since it uses less digits than its factorization.

681728256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 797 (or 780 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 681728256 is about 26109.9263882532. The cubic root of 681728256 is about 880.1102892073.

The spelling of 681728256 in words is "six hundred eighty-one million, seven hundred twenty-eight thousand, two hundred fifty-six".