4394521 has 4 divisors (see below), whose sum is σ = 4398772. Its totient is φ = 4390272.

The previous prime is 4394473. The next prime is 4394561. The reversal of 4394521 is 1254934.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 2768896 + 1625625 = 1664^2 + 1275^2 .

It is a cyclic number.

It is not a de Polignac number, because 4394521 - 2¹¹ = 4392473 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 4394521.

It is not an unprimeable number, because it can be changed into a prime (4394561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 541 + ... + 3013.

It is an arithmetic number, because the mean of its divisors is an integer number (1099693).

Almost surely, 2^4394521 is an apocalyptic number.

It is an amenable number.

4394521 is a deficient number, since it is larger than the sum of its proper divisors (4251).

4394521 is a wasteful number, since it uses less digits than its factorization.

4394521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4250.

The product of its digits is 4320, while the sum is 28.

The square root of 4394521 is about 2096.3112841370. The cubic root of 4394521 is about 163.7962097893.

It can be divided in two parts, 439452 and 1, that added together give a triangular number (439453 = T₉₃₇).

The spelling of 4394521 in words is "four million, three hundred ninety-four thousand, five hundred twenty-one".