681111444 has 48 divisors (see below), whose sum is σ = 1724627520. Its totient is φ = 207966720.

The previous prime is 681111419. The next prime is 681111463. The reversal of 681111444 is 444111186.

681111444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3772 + ... + 37100.

It is an arithmetic number, because the mean of its divisors is an integer number (35929740).

Almost surely, 2^681111444 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 681111444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (862313760).

681111444 is an abundant number, since it is smaller than the sum of its proper divisors (1043516076).

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

681111444 is a wasteful number, since it uses less digits than its factorization.

681111444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33480 (or 33478 counting only the distinct ones).

The product of its digits is 3072, while the sum is 30.

The square root of 681111444 is about 26098.1118857284. Note that the first 3 decimals coincide. The cubic root of 681111444 is about 879.8447746183.

The spelling of 681111444 in words is "six hundred eighty-one million, one hundred eleven thousand, four hundred forty-four".