6421816 has 16 divisors (see below), whose sum is σ = 12221640. Its totient is φ = 3162720.

The previous prime is 6421799. The next prime is 6421817. The reversal of 6421816 is 6181246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6421817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5455 + ... + 6526.

Almost surely, 2^6421816 is an apocalyptic number.

It is an amenable number.

6421816 is a deficient number, since it is larger than the sum of its proper divisors (5799824).

6421816 is a wasteful number, since it uses less digits than its factorization.

6421816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12054 (or 12050 counting only the distinct ones).

The product of its digits is 2304, while the sum is 28.

The square root of 6421816 is about 2534.1302255409. The cubic root of 6421816 is about 185.8742743064.

The spelling of 6421816 in words is "six million, four hundred twenty-one thousand, eight hundred sixteen".