404721 has 12 divisors (see below), whose sum is σ = 590148. Its totient is φ = 267264.

The previous prime is 404713. The next prime is 404773. The reversal of 404721 is 127404.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 90000 + 314721 = 300^2 + 561^2 .

It is not a de Polignac number, because 404721 - 2³ = 404713 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 404694 and 404703.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 404721.

It is not an unprimeable number, because it can be changed into a prime (404021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1621 + ... + 1853.

It is an arithmetic number, because the mean of its divisors is an integer number (49179).

2⁴⁰⁴⁷²¹ is an apocalyptic number.

It is an amenable number.

404721 is a deficient number, since it is larger than the sum of its proper divisors (185427).

404721 is a wasteful number, since it uses less digits than its factorization.

404721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432 (or 429 counting only the distinct ones).

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

The square root of 404721 is about 636.1768622011. The cubic root of 404721 is about 73.9693688662.

It can be divided in two parts, 40 and 4721, that added together give a square (4761 = 69²).

The spelling of 404721 in words is "four hundred four thousand, seven hundred twenty-one", and thus it is an iban number.