681332736 has 156 divisors (see below), whose sum is σ = 2099779232. Its totient is φ = 192479232.

The previous prime is 681332719. The next prime is 681332741. The reversal of 681332736 is 637233186.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 681332694 and 681332703.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7655380 + ... + 7655468.

Almost surely, 2^681332736 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 681332736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1049889616).

681332736 is an abundant number, since it is smaller than the sum of its proper divisors (1418446496).

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

681332736 is an frugal number, since it uses more digits than its factorization.

681332736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212 (or 101 counting only the distinct ones).

The product of its digits is 108864, while the sum is 39.

The square root of 681332736 is about 26102.3511584685. The cubic root of 681332736 is about 879.9400510126.

Multiplying 681332736 by its product of digits (108864), we get a square (74172606971904 = 8612352²).

The spelling of 681332736 in words is "six hundred eighty-one million, three hundred thirty-two thousand, seven hundred thirty-six".