1812215 has 4 divisors (see below), whose sum is σ = 2174664. Its totient is φ = 1449768.

The previous prime is 1812199. The next prime is 1812227. The reversal of 1812215 is 5122181.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1812215 - 2⁴ = 1812199 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 181217 + ... + 181226.

It is an arithmetic number, because the mean of its divisors is an integer number (543666).

2^1812215 is an apocalyptic number.

1812215 is a deficient number, since it is larger than the sum of its proper divisors (362449).

1812215 is an equidigital number, since it uses as much as digits as its factorization.

1812215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362448.

The product of its digits is 160, while the sum is 20.

The square root of 1812215 is about 1346.1853512797. The cubic root of 1812215 is about 121.9185831415.

Adding to 1812215 its reverse (5122181), we get a palindrome (6934396).

The spelling of 1812215 in words is "one million, eight hundred twelve thousand, two hundred fifteen".