681803 has 4 divisors (see below), whose sum is σ = 683880. Its totient is φ = 679728.

The previous prime is 681787. The next prime is 681809. The reversal of 681803 is 308186.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 681803 - 2⁴ = 681787 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (681809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 425 + ... + 1242.

It is an arithmetic number, because the mean of its divisors is an integer number (170970).

2⁶⁸¹⁸⁰³ is an apocalyptic number.

681803 is a deficient number, since it is larger than the sum of its proper divisors (2077).

681803 is a wasteful number, since it uses less digits than its factorization.

681803 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2076.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 681803 is about 825.7136307462. The cubic root of 681803 is about 88.0142452834.

Adding to 681803 its reverse (308186), we get a palindrome (989989).

The spelling of 681803 in words is "six hundred eighty-one thousand, eight hundred three".