681980 has 48 divisors (see below), whose sum is σ = 1604064. Its totient is φ = 241920.

The previous prime is 681979. The next prime is 681983. The reversal of 681980 is 89186.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681983) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 11150 + ... + 11210.

It is an arithmetic number, because the mean of its divisors is an integer number (33418).

2⁶⁸¹⁹⁸⁰ 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 681980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (802032).

681980 is an abundant number, since it is smaller than the sum of its proper divisors (922084).

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

681980 is a wasteful number, since it uses less digits than its factorization.

681980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 681980 is about 825.8208038067. The cubic root of 681980 is about 88.0218609600.

It can be divided in two parts, 681 and 980, that added together give a palindrome (1661).

The spelling of 681980 in words is "six hundred eighty-one thousand, nine hundred eighty".