8440638 has 8 divisors (see below), whose sum is σ = 16881288. Its totient is φ = 2813544.

The previous prime is 8440637. The next prime is 8440639. The reversal of 8440638 is 8360448.

It is an interprime number because it is at equal distance from previous prime (8440637) and next prime (8440639).

It is a sphenic number, since it is the product of 3 distinct primes.

8440638 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 8440599 and 8440608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8440637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 703381 + ... + 703392.

It is an arithmetic number, because the mean of its divisors is an integer number (2110161).

Almost surely, 2^8440638 is an apocalyptic number.

8440638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

8440638 is a wasteful number, since it uses less digits than its factorization.

8440638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1406778.

The product of its (nonzero) digits is 18432, while the sum is 33.

The square root of 8440638 is about 2905.2776115201. The cubic root of 8440638 is about 203.6065561683.

The spelling of 8440638 in words is "eight million, four hundred forty thousand, six hundred thirty-eight".