721061 has 4 divisors (see below), whose sum is σ = 786624. Its totient is φ = 655500.

The previous prime is 721057. The next prime is 721079. The reversal of 721061 is 160127.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 160127 = 11 ⋅14557.

It is a cyclic number.

It is not a de Polignac number, because 721061 - 2² = 721057 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 721061.

It is not an unprimeable number, because it can be changed into a prime (721051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32765 + ... + 32786.

It is an arithmetic number, because the mean of its divisors is an integer number (196656).

2⁷²¹⁰⁶¹ is an apocalyptic number.

It is an amenable number.

721061 is a deficient number, since it is larger than the sum of its proper divisors (65563).

721061 is a wasteful number, since it uses less digits than its factorization.

721061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65562.

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

The square root of 721061 is about 849.1531075136. The cubic root of 721061 is about 89.6720989755.

Adding to 721061 its reverse (160127), we get a palindrome (881188).

The spelling of 721061 in words is "seven hundred twenty-one thousand, sixty-one".