681400 has 24 divisors (see below), whose sum is σ = 1584720. Its totient is φ = 272480.

The previous prime is 681371. The next prime is 681403. The reversal of 681400 is 4186.

681400 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 not an unprimeable number, because it can be changed into a prime (681403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1504 + ... + 1903.

It is an arithmetic number, because the mean of its divisors is an integer number (66030).

2⁶⁸¹⁴⁰⁰ is an apocalyptic number.

It is an amenable number.

681400 is an abundant number, since it is smaller than the sum of its proper divisors (903320).

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

681400 is a wasteful number, since it uses less digits than its factorization.

681400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3423 (or 3414 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 681400 is about 825.4695633396. The cubic root of 681400 is about 87.9969007173.

Adding to 681400 its reverse (4186), we get a palindrome (685586).

It can be divided in two parts, 681 and 400, that added together give a triangular number (1081 = T₄₆).

The spelling of 681400 in words is "six hundred eighty-one thousand, four hundred".