4004721 has 30 divisors (see below), whose sum is σ = 6965970. Its totient is φ = 2286144.

The previous prime is 4004717. The next prime is 4004731. The reversal of 4004721 is 1274004.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 3111696 + 893025 = 1764^2 + 945^2 .

It is not a de Polignac number, because 4004721 - 2² = 4004717 is a prime.

4004721 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 4004694 and 4004703.

It is not an unprimeable number, because it can be changed into a prime (4004731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 3465 + ... + 4473.

It is an arithmetic number, because the mean of its divisors is an integer number (232199).

Almost surely, 2^4004721 is an apocalyptic number.

It is an amenable number.

4004721 is a deficient number, since it is larger than the sum of its proper divisors (2961249).

4004721 is a wasteful number, since it uses less digits than its factorization.

4004721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1035 (or 1019 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 4004721 is about 2001.1799019578. The cubic root of 4004721 is about 158.8025316467.

Adding to 4004721 its reverse (1274004), we get a palindrome (5278725).

The spelling of 4004721 in words is "four million, four thousand, seven hundred twenty-one".