338640 has 80 divisors (see below), whose sum is σ = 1124928. Its totient is φ = 83968.

The previous prime is 338609. The next prime is 338659. The reversal of 338640 is 46833.

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

It is a super-2 number, since 2×338640² = 229354099200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 338640.

It is a congruent number.

It is an unprimeable number.

338640 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4039 + ... + 4121.

2³³⁸⁶⁴⁰ is an apocalyptic number.

338640 is a gapful number since it is divisible by the number (30) 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 338640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (562464).

338640 is an abundant number, since it is smaller than the sum of its proper divisors (786288).

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

338640 is a wasteful number, since it uses less digits than its factorization.

338640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116 (or 110 counting only the distinct ones).

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

The square root of 338640 is about 581.9278305770. The cubic root of 338640 is about 69.7021356848.

The spelling of 338640 in words is "three hundred thirty-eight thousand, six hundred forty".