681503 has 8 divisors (see below), whose sum is σ = 710448. Its totient is φ = 653184.

The previous prime is 681497. The next prime is 681521. The reversal of 681503 is 305186.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 681503 - 2⁴ = 681487 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681523) 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 7 ways as a sum of consecutive naturals, for example, 4100 + ... + 4262.

It is an arithmetic number, because the mean of its divisors is an integer number (88806).

2⁶⁸¹⁵⁰³ is an apocalyptic number.

681503 is a deficient number, since it is larger than the sum of its proper divisors (28945).

681503 is a wasteful number, since it uses less digits than its factorization.

681503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 681503 is about 825.5319497148. The cubic root of 681503 is about 88.0013343462.

Adding to 681503 its reverse (305186), we get a palindrome (986689).

The spelling of 681503 in words is "six hundred eighty-one thousand, five hundred three".