681394 has 24 divisors (see below), whose sum is σ = 1261980. Its totient is φ = 274176.

The previous prime is 681371. The next prime is 681403. The reversal of 681394 is 493186.

681394 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 582169 + 99225 = 763^2 + 315^2 .

It is an unprimeable number.

681394 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1462 + ... + 1870.

2⁶⁸¹³⁹⁴ is an apocalyptic number.

681394 is a deficient number, since it is larger than the sum of its proper divisors (580586).

681394 is a wasteful number, since it uses less digits than its factorization.

681394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 442 (or 435 counting only the distinct ones).

The product of its digits is 5184, while the sum is 31.

The square root of 681394 is about 825.4659290364. The cubic root of 681394 is about 87.9966424339.

The spelling of 681394 in words is "six hundred eighty-one thousand, three hundred ninety-four".