5643521 has 4 divisors (see below), whose sum is σ = 6077652. Its totient is φ = 5209392.

The previous prime is 5643509. The next prime is 5643529. The reversal of 5643521 is 1253465.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1253465 = 5 ⋅250693.

It can be written as a sum of positive squares in 2 ways, for example, as 1860496 + 3783025 = 1364^2 + 1945^2 .

It is a cyclic number.

It is not a de Polignac number, because 5643521 - 2¹⁸ = 5381377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5643529) 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, 217046 + ... + 217071.

It is an arithmetic number, because the mean of its divisors is an integer number (1519413).

Almost surely, 2^5643521 is an apocalyptic number.

It is an amenable number.

5643521 is a deficient number, since it is larger than the sum of its proper divisors (434131).

5643521 is a wasteful number, since it uses less digits than its factorization.

5643521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434130.

The product of its digits is 3600, while the sum is 26.

The square root of 5643521 is about 2375.6096059749. The cubic root of 5643521 is about 178.0396431502.

Adding to 5643521 its reverse (1253465), we get a palindrome (6896986).

The spelling of 5643521 in words is "five million, six hundred forty-three thousand, five hundred twenty-one".