4445721 has 36 divisors (see below), whose sum is σ = 7922772. Its totient is φ = 2386944.

The previous prime is 4445719. The next prime is 4445723. The reversal of 4445721 is 1275444.

It is an interprime number because it is at equal distance from previous prime (4445719) and next prime (4445723).

It can be written as a sum of positive squares in 2 ways, for example, as 3111696 + 1334025 = 1764^2 + 1155^2 .

It is not a de Polignac number, because 4445721 - 2¹ = 4445719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4445723) 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 35 ways as a sum of consecutive naturals, for example, 7201 + ... + 7793.

It is an arithmetic number, because the mean of its divisors is an integer number (220077).

Almost surely, 2^4445721 is an apocalyptic number.

It is an amenable number.

4445721 is a deficient number, since it is larger than the sum of its proper divisors (3477051).

4445721 is a wasteful number, since it uses less digits than its factorization.

4445721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 630 (or 620 counting only the distinct ones).

The product of its digits is 4480, while the sum is 27.

The square root of 4445721 is about 2108.4878467755. The cubic root of 4445721 is about 164.4298780655.

The spelling of 4445721 in words is "four million, four hundred forty-five thousand, seven hundred twenty-one".