6643420 has 36 divisors (see below), whose sum is σ = 16231320. Its totient is φ = 2277408.

The previous prime is 6643411. The next prime is 6643423. The reversal of 6643420 is 243466.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6643423) 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, 2410 + ... + 4369.

It is an arithmetic number, because the mean of its divisors is an integer number (450870).

Almost surely, 2^6643420 is an apocalyptic number.

It is an amenable number.

6643420 is an abundant number, since it is smaller than the sum of its proper divisors (9587900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6643420 is a wasteful number, since it uses less digits than its factorization.

6643420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6802 (or 6793 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 6643420 is about 2577.4832686169. The cubic root of 6643420 is about 187.9881915022.

Adding to 6643420 its reverse (243466), we get a palindrome (6886886).

The spelling of 6643420 in words is "six million, six hundred forty-three thousand, four hundred twenty".