1388240 has 80 divisors (see below), whose sum is σ = 3844992. Its totient is φ = 456192.

The previous prime is 1388227. The next prime is 1388243. The reversal of 1388240 is 428831.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1388243) 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, 20687 + ... + 20753.

2^1388240 is an apocalyptic number.

1388240 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 1388240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1922496).

1388240 is an abundant number, since it is smaller than the sum of its proper divisors (2456752).

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

1388240 is a wasteful number, since it uses less digits than its factorization.

1388240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 1388240 is about 1178.2359695749. The cubic root of 1388240 is about 111.5547801363.

The spelling of 1388240 in words is "one million, three hundred eighty-eight thousand, two hundred forty".