8421644 has 48 divisors (see below), whose sum is σ = 18896640. Its totient is φ = 3188160.

The previous prime is 8421641. The next prime is 8421653. The reversal of 8421644 is 4461248.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8421641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11027 + ... + 11765.

It is an arithmetic number, because the mean of its divisors is an integer number (393680).

Almost surely, 2^8421644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8421644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9448320).

8421644 is an abundant number, since it is smaller than the sum of its proper divisors (10474996).

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

8421644 is a wasteful number, since it uses less digits than its factorization.

8421644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 798 (or 796 counting only the distinct ones).

The product of its digits is 6144, while the sum is 29.

The square root of 8421644 is about 2902.0068917906. The cubic root of 8421644 is about 203.4537159277.

The spelling of 8421644 in words is "eight million, four hundred twenty-one thousand, six hundred forty-four".