681573 has 4 divisors (see below), whose sum is σ = 908768. Its totient is φ = 454380.

The previous prime is 681563. The next prime is 681589. The reversal of 681573 is 375186.

681573 is nontrivially palindromic in base 2.

681573 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 681573 - 2⁴ = 681557 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 681573.

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 polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113593 + ... + 113598.

It is an arithmetic number, because the mean of its divisors is an integer number (227192).

681573 is a Friedman number, since it can be written as (13*8^6-7)/5, using all its digits and the basic arithmetic operations.

2⁶⁸¹⁵⁷³ is an apocalyptic number.

It is an amenable number.

681573 is a deficient number, since it is larger than the sum of its proper divisors (227195).

681573 is a wasteful number, since it uses less digits than its factorization.

681573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227194.

The product of its digits is 5040, while the sum is 30.

The square root of 681573 is about 825.5743455316. The cubic root of 681573 is about 88.0043472370.

The spelling of 681573 in words is "six hundred eighty-one thousand, five hundred seventy-three".