638000 has 80 divisors (see below), whose sum is σ = 1740960. Its totient is φ = 224000.

The previous prime is 637939. The next prime is 638023. The reversal of 638000 is 836.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 638000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21986 + ... + 22014.

It is an arithmetic number, because the mean of its divisors is an integer number (21762).

2⁶³⁸⁰⁰⁰ 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 638000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (870480).

638000 is an abundant number, since it is smaller than the sum of its proper divisors (1102960).

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

638000 is a wasteful number, since it uses less digits than its factorization.

638000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63 (or 47 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 638000 is about 798.7490219086. The cubic root of 638000 is about 86.0875258181.

Adding to 638000 its reverse (836), we get a palindrome (638836).

The spelling of 638000 in words is "six hundred thirty-eight thousand".