1389440 has 64 divisors (see below), whose sum is σ = 3598560. Its totient is φ = 509952.

The previous prime is 1389439. The next prime is 1389469. The reversal of 1389440 is 449831.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8237 + ... + 8403.

2^1389440 is an apocalyptic number.

1389440 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 1389440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1799280).

1389440 is an abundant number, since it is smaller than the sum of its proper divisors (2209120).

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

1389440 is a wasteful number, since it uses less digits than its factorization.

1389440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199 (or 187 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 1389440 is about 1178.7450954299. The cubic root of 1389440 is about 111.5869136730.

The spelling of 1389440 in words is "one million, three hundred eighty-nine thousand, four hundred forty".