1812845 has 4 divisors (see below), whose sum is σ = 2175420. Its totient is φ = 1450272.

The previous prime is 1812827. The next prime is 1812851. The reversal of 1812845 is 5482181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 515524 + 1297321 = 718^2 + 1139^2 .

It is a cyclic number.

It is not a de Polignac number, because 1812845 - 2⁸ = 1812589 is a prime.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 181280 + ... + 181289.

It is an arithmetic number, because the mean of its divisors is an integer number (543855).

2^1812845 is an apocalyptic number.

It is an amenable number.

1812845 is a deficient number, since it is larger than the sum of its proper divisors (362575).

1812845 is an equidigital number, since it uses as much as digits as its factorization.

1812845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362574.

The product of its digits is 2560, while the sum is 29.

The square root of 1812845 is about 1346.4193254703. The cubic root of 1812845 is about 121.9327094654.

The spelling of 1812845 in words is "one million, eight hundred twelve thousand, eight hundred forty-five".