5605721 has 8 divisors (see below), whose sum is σ = 6381504. Its totient is φ = 4874320.

The previous prime is 5605711. The next prime is 5605739. The reversal of 5605721 is 1275065.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-5605721 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5605711) 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, 10826 + ... + 11331.

It is an arithmetic number, because the mean of its divisors is an integer number (797688).

Almost surely, 2^5605721 is an apocalyptic number.

It is an amenable number.

5605721 is a deficient number, since it is larger than the sum of its proper divisors (775783).

5605721 is a wasteful number, since it uses less digits than its factorization.

5605721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22191.

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 5605721 is about 2367.6403865452. The cubic root of 5605721 is about 177.6412523718.

The spelling of 5605721 in words is "five million, six hundred five thousand, seven hundred twenty-one".