726681 has 4 divisors (see below), whose sum is σ = 968912. Its totient is φ = 484452.

The previous prime is 726679. The next prime is 726689. The reversal of 726681 is 186627.

It is a happy number.

726681 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 726681 - 2¹ = 726679 is a prime.

It is a super-2 number, since 2×726681² = 1056130551522, which contains 22 as substring.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 726681.

It is not an unprimeable number, because it can be changed into a prime (726689) 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, 121111 + ... + 121116.

It is an arithmetic number, because the mean of its divisors is an integer number (242228).

2⁷²⁶⁶⁸¹ is an apocalyptic number.

It is an amenable number.

726681 is a deficient number, since it is larger than the sum of its proper divisors (242231).

726681 is a wasteful number, since it uses less digits than its factorization.

726681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242230.

The product of its digits is 4032, while the sum is 30.

The square root of 726681 is about 852.4558639601. The cubic root of 726681 is about 89.9044665300.

The spelling of 726681 in words is "seven hundred twenty-six thousand, six hundred eighty-one".