681923 has 8 divisors (see below), whose sum is σ = 760320. Its totient is φ = 606280.

The previous prime is 681913. The next prime is 681931. The reversal of 681923 is 329186.

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 681923 - 2¹² = 677827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (681913) 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, 143 + ... + 1176.

It is an arithmetic number, because the mean of its divisors is an integer number (95040).

2⁶⁸¹⁹²³ is an apocalyptic number.

681923 is a deficient number, since it is larger than the sum of its proper divisors (78397).

681923 is a wasteful number, since it uses less digits than its factorization.

681923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1377.

The product of its digits is 2592, while the sum is 29.

The square root of 681923 is about 825.7862919666. The cubic root of 681923 is about 88.0194085979.

It can be divided in two parts, 68 and 1923, that added together give a palindrome (1991).

The spelling of 681923 in words is "six hundred eighty-one thousand, nine hundred twenty-three".