681896 has 8 divisors (see below), whose sum is σ = 1278570. Its totient is φ = 340944.

The previous prime is 681883. The next prime is 681899. The reversal of 681896 is 698186.

681896 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 only one way, i.e., 532900 + 148996 = 730^2 + 386^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (681899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42611 + ... + 42626.

2⁶⁸¹⁸⁹⁶ is an apocalyptic number.

It is an amenable number.

681896 is a deficient number, since it is larger than the sum of its proper divisors (596674).

681896 is a wasteful number, since it uses less digits than its factorization.

681896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85243 (or 85239 counting only the distinct ones).

The product of its digits is 20736, while the sum is 38.

The square root of 681896 is about 825.7699437495. The cubic root of 681896 is about 88.0182469049.

Subtracting 681896 from its reverse (698186), we obtain a triangular number (16290 = T₁₈₀).

The spelling of 681896 in words is "six hundred eighty-one thousand, eight hundred ninety-six".