1812145 has 4 divisors (see below), whose sum is σ = 2174580. Its totient is φ = 1449712.

The previous prime is 1812137. The next prime is 1812157. The reversal of 1812145 is 5412181.

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 1437601 + 374544 = 1199^2 + 612^2 .

It is a cyclic number.

It is not a de Polignac number, because 1812145 - 2³ = 1812137 is a prime.

It is an alternating number because its digits alternate between odd and even.

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, 181210 + ... + 181219.

It is an arithmetic number, because the mean of its divisors is an integer number (543645).

2^1812145 is an apocalyptic number.

It is an amenable number.

1812145 is a deficient number, since it is larger than the sum of its proper divisors (362435).

1812145 is an equidigital number, since it uses as much as digits as its factorization.

1812145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362434.

The product of its digits is 320, while the sum is 22.

The square root of 1812145 is about 1346.1593516371. The cubic root of 1812145 is about 121.9170133479.

The spelling of 1812145 in words is "one million, eight hundred twelve thousand, one hundred forty-five".