6408221 has 4 divisors (see below), whose sum is σ = 6414432. Its totient is φ = 6402012.

The previous prime is 6408211. The next prime is 6408223. The reversal of 6408221 is 1228046.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 6408221 - 2¹⁰ = 6407197 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6408223) 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, 1145 + ... + 3758.

It is an arithmetic number, because the mean of its divisors is an integer number (1603608).

Almost surely, 2^6408221 is an apocalyptic number.

It is an amenable number.

6408221 is a deficient number, since it is larger than the sum of its proper divisors (6211).

6408221 is a wasteful number, since it uses less digits than its factorization.

6408221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6210.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 6408221 is about 2531.4464244775. The cubic root of 6408221 is about 185.7430162088.

The spelling of 6408221 in words is "six million, four hundred eight thousand, two hundred twenty-one".