6421656 has 16 divisors (see below), whose sum is σ = 16054200. Its totient is φ = 2140544.

The previous prime is 6421643. The next prime is 6421697. The reversal of 6421656 is 6561246.

6421656 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133761 + ... + 133808.

Almost surely, 2^6421656 is an apocalyptic number.

It is an amenable number.

6421656 is an abundant number, since it is smaller than the sum of its proper divisors (9632544).

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

6421656 is a wasteful number, since it uses less digits than its factorization.

6421656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 267578 (or 267574 counting only the distinct ones).

The product of its digits is 8640, while the sum is 30.

The square root of 6421656 is about 2534.0986563273. The cubic root of 6421656 is about 185.8727306033.

The spelling of 6421656 in words is "six million, four hundred twenty-one thousand, six hundred fifty-six".