681796440 has 160 divisors (see below), whose sum is σ = 2468022480. Its totient is φ = 167816448.

The previous prime is 681796397. The next prime is 681796481. The reversal of 681796440 is 44697186.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 34027 + ... + 50213.

Almost surely, 2^681796440 is an apocalyptic number.

681796440 is a gapful number since it is divisible by the number (60) 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 681796440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1234011240).

681796440 is an abundant number, since it is smaller than the sum of its proper divisors (1786226040).

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

681796440 is a wasteful number, since it uses less digits than its factorization.

681796440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16223 (or 16210 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 45.

The square root of 681796440 is about 26111.2320659137. The cubic root of 681796440 is about 880.1396300475.

The spelling of 681796440 in words is "six hundred eighty-one million, seven hundred ninety-six thousand, four hundred forty".