1438640 has 60 divisors (see below), whose sum is σ = 3901536. Its totient is φ = 491904.

The previous prime is 1438609. The next prime is 1438643. The reversal of 1438640 is 468341.

It is not an unprimeable number, because it can be changed into a prime (1438643) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3737 + ... + 4103.

2^1438640 is an apocalyptic number.

1438640 is a gapful number since it is divisible by the number (10) 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 1438640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1950768).

1438640 is an abundant number, since it is smaller than the sum of its proper divisors (2462896).

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

1438640 is a wasteful number, since it uses less digits than its factorization.

1438640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394 (or 381 counting only the distinct ones).

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

The square root of 1438640 is about 1199.4331994738. The cubic root of 1438640 is about 112.8887620181. Note that the first 3 decimals are identical.

Subtracting from 1438640 its reverse (468341), we obtain a cube (970299 = 99³).

The spelling of 1438640 in words is "one million, four hundred thirty-eight thousand, six hundred forty".