1816225 has 6 divisors (see below), whose sum is σ = 2252150. Its totient is φ = 1452960.

The previous prime is 1816211. The next prime is 1816237. The reversal of 1816225 is 5226181.

It can be written as a sum of positive squares in 3 ways, for example, as 31329 + 1784896 = 177^2 + 1336^2 .

It is not a de Polignac number, because 1816225 - 2⁵ = 1816193 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 72649 = 1816225 / (1 + 8 + 1 + 6 + 2 + 2 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 1816225.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36300 + ... + 36349.

2^1816225 is an apocalyptic number.

It is an amenable number.

1816225 is a deficient number, since it is larger than the sum of its proper divisors (435925).

1816225 is an equidigital number, since it uses as much as digits as its factorization.

1816225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72659 (or 72654 counting only the distinct ones).

The product of its digits is 960, while the sum is 25.

The square root of 1816225 is about 1347.6739219856. The cubic root of 1816225 is about 122.0084424866.

The spelling of 1816225 in words is "one million, eight hundred sixteen thousand, two hundred twenty-five".