1866384 has 60 divisors (see below), whose sum is σ = 5630716. Its totient is φ = 573696.

The previous prime is 1866373. The next prime is 1866409. The reversal of 1866384 is 4836681.

It is a happy number.

1866384 is a `hidden beast` number, since 18 + 6 + 638 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 944784 + 921600 = 972^2 + 960^2 .

It is a super-3 number, since 3×1866384³ = 19504025804481933312, which contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

Its product of digits (27648) is a multiple of the sum of its prime factors (1024).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1374 + ... + 2370.

2^1866384 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 1866384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2815358).

1866384 is an abundant number, since it is smaller than the sum of its proper divisors (3764332).

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

1866384 is a wasteful number, since it uses less digits than its factorization.

1866384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1024 (or 1015 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 1866384 is about 1366.1566528038. The cubic root of 1866384 is about 123.1214347014.

Subtracting from 1866384 its product of digits (27648), we obtain a square (1838736 = 1356²).

The spelling of 1866384 in words is "one million, eight hundred sixty-six thousand, three hundred eighty-four".