601721 has 4 divisors (see below), whose sum is σ = 622500. Its totient is φ = 580944.

The previous prime is 601717. The next prime is 601747. The reversal of 601721 is 127106.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 132496 + 469225 = 364^2 + 685^2 .

It is a cyclic number.

It is not a de Polignac number, because 601721 - 2² = 601717 is a prime.

It is a super-3 number, since 3×601721³ = 653592049233385083, which contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 601721.

It is not an unprimeable number, because it can be changed into a prime (601751) 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, 10346 + ... + 10403.

It is an arithmetic number, because the mean of its divisors is an integer number (155625).

2⁶⁰¹⁷²¹ is an apocalyptic number.

It is an amenable number.

601721 is a deficient number, since it is larger than the sum of its proper divisors (20779).

601721 is a wasteful number, since it uses less digits than its factorization.

601721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20778.

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 601721 is about 775.7067744967. The cubic root of 601721 is about 84.4238310848.

Adding to 601721 its reverse (127106), we get a palindrome (728827).

The spelling of 601721 in words is "six hundred one thousand, seven hundred twenty-one".