5643421 has 4 divisors (see below), whose sum is σ = 6449632. Its totient is φ = 4837212.

The previous prime is 5643413. The next prime is 5643427. The reversal of 5643421 is 1243465.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 5643421 - 2³ = 5643413 is a prime.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5643427) 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, 403095 + ... + 403108.

It is an arithmetic number, because the mean of its divisors is an integer number (1612408).

Almost surely, 2^5643421 is an apocalyptic number.

It is an amenable number.

5643421 is a deficient number, since it is larger than the sum of its proper divisors (806211).

5643421 is an equidigital number, since it uses as much as digits as its factorization.

5643421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 806210.

The product of its digits is 2880, while the sum is 25.

The square root of 5643421 is about 2375.5885586524. The cubic root of 5643421 is about 178.0385915567.

Adding to 5643421 its reverse (1243465), we get a palindrome (6886886).

The spelling of 5643421 in words is "five million, six hundred forty-three thousand, four hundred twenty-one".