638120 has 64 divisors (see below), whose sum is σ = 1710720. Its totient is φ = 209664.

The previous prime is 638117. The next prime is 638123. The reversal of 638120 is 21836.

638120 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (638117) and next prime (638123).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 638092 and 638101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12014 + ... + 12066.

It is an arithmetic number, because the mean of its divisors is an integer number (26730).

2⁶³⁸¹²⁰ 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 638120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (855360).

638120 is an abundant number, since it is smaller than the sum of its proper divisors (1072600).

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

638120 is a wasteful number, since it uses less digits than its factorization.

638120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 110 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 638120 is about 798.8241358397. The cubic root of 638120 is about 86.0929228167.

Adding to 638120 its reverse (21836), we get a palindrome (659956).

The spelling of 638120 in words is "six hundred thirty-eight thousand, one hundred twenty".