1866388 has 12 divisors (see below), whose sum is σ = 3276532. Its totient is φ = 930240.

The previous prime is 1866373. The next prime is 1866409. The reversal of 1866388 is 8836681.

It can be written as a sum of positive squares in 2 ways, for example, as 1373584 + 492804 = 1172^2 + 702^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1866388.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1318 + ... + 2338.

2^1866388 is an apocalyptic number.

It is an amenable number.

1866388 is a deficient number, since it is larger than the sum of its proper divisors (1410144).

1866388 is a wasteful number, since it uses less digits than its factorization.

1866388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1482 (or 1480 counting only the distinct ones).

The product of its digits is 55296, while the sum is 40.

The square root of 1866388 is about 1366.1581167639. The cubic root of 1866388 is about 123.1215226585.

The spelling of 1866388 in words is "one million, eight hundred sixty-six thousand, three hundred eighty-eight".