1866945 has 16 divisors (see below), whose sum is σ = 3030912. Its totient is φ = 981120.

The previous prime is 1866941. The next prime is 1866961. The reversal of 1866945 is 5496681.

It is not a de Polignac number, because 1866945 - 2² = 1866941 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1866941) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 189 + ... + 1941.

It is an arithmetic number, because the mean of its divisors is an integer number (189432).

2^1866945 is an apocalyptic number.

1866945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1866945 is a deficient number, since it is larger than the sum of its proper divisors (1163967).

1866945 is a wasteful number, since it uses less digits than its factorization.

1866945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1832.

The product of its digits is 51840, while the sum is 39.

The square root of 1866945 is about 1366.3619579013. The cubic root of 1866945 is about 123.1337694631.

The spelling of 1866945 in words is "one million, eight hundred sixty-six thousand, nine hundred forty-five".