1398784 has 24 divisors (see below), whose sum is σ = 2800980. Its totient is φ = 698368.

The previous prime is 1398781. The next prime is 1398841. The reversal of 1398784 is 4878931.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1398781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1707 + ... + 2389.

2^1398784 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1398784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1400490).

1398784 is an abundant number, since it is smaller than the sum of its proper divisors (1402196).

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

1398784 is an frugal number, since it uses more digits than its factorization.

1398784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705 (or 685 counting only the distinct ones).

The product of its digits is 48384, while the sum is 40.

The square root of 1398784 is about 1182.7019912049. The cubic root of 1398784 is about 111.8364961179.

The spelling of 1398784 in words is "one million, three hundred ninety-eight thousand, seven hundred eighty-four".