638144 has 42 divisors (see below), whose sum is σ = 1394460. Its totient is φ = 289536.

The previous prime is 638123. The next prime is 638147. The reversal of 638144 is 441836.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is not an unprimeable number, because it can be changed into a prime (638147) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10787 + ... + 10845.

2⁶³⁸¹⁴⁴ is an apocalyptic number.

638144 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (697230).

638144 is an abundant number, since it is smaller than the sum of its proper divisors (756316).

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

638144 is a wasteful number, since it uses less digits than its factorization.

638144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 74 counting only the distinct ones).

The product of its digits is 2304, while the sum is 26.

The square root of 638144 is about 798.8391577783. The cubic root of 638144 is about 86.0940021353.

The spelling of 638144 in words is "six hundred thirty-eight thousand, one hundred forty-four".