1866444 has 12 divisors (see below), whose sum is σ = 4355064. Its totient is φ = 622144.

The previous prime is 1866439. The next prime is 1866451. The reversal of 1866444 is 4446681.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×1866444² = 6967226410272, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77757 + ... + 77780.

It is an arithmetic number, because the mean of its divisors is an integer number (362922).

2^1866444 is an apocalyptic number.

It is an amenable number.

1866444 is an abundant number, since it is smaller than the sum of its proper divisors (2488620).

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

1866444 is a wasteful number, since it uses less digits than its factorization.

1866444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155544 (or 155542 counting only the distinct ones).

The product of its digits is 18432, while the sum is 33.

The square root of 1866444 is about 1366.1786120416. The cubic root of 1866444 is about 123.1227540453.

The spelling of 1866444 in words is "one million, eight hundred sixty-six thousand, four hundred forty-four".