638340 has 24 divisors (see below), whose sum is σ = 1787520. Its totient is φ = 170208.

The previous prime is 638327. The next prime is 638347. The reversal of 638340 is 43836.

638340 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 638340.

It is not an unprimeable number, because it can be changed into a prime (638347) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5260 + ... + 5379.

It is an arithmetic number, because the mean of its divisors is an integer number (74480).

2⁶³⁸³⁴⁰ is an apocalyptic number.

638340 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

638340 is an abundant number, since it is smaller than the sum of its proper divisors (1149180).

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

638340 is a wasteful number, since it uses less digits than its factorization.

638340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10651 (or 10649 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 638340 is about 798.9618263722. The cubic root of 638340 is about 86.1028155573.

The spelling of 638340 in words is "six hundred thirty-eight thousand, three hundred forty".