1811825 has 18 divisors (see below), whose sum is σ = 2365734. Its totient is φ = 1376320.

The previous prime is 1811819. The next prime is 1811827. The reversal of 1811825 is 5281181.

It can be written as a sum of positive squares in 3 ways, for example, as 152881 + 1658944 = 391^2 + 1288^2 .

It is not a de Polignac number, because 1811825 - 2⁸ = 1811569 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1811794 and 1811803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1811827) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 13157 + ... + 13293.

2^1811825 is an apocalyptic number.

It is an amenable number.

1811825 is a deficient number, since it is larger than the sum of its proper divisors (553909).

1811825 is a wasteful number, since it uses less digits than its factorization.

1811825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193 (or 165 counting only the distinct ones).

The product of its digits is 640, while the sum is 26.

The square root of 1811825 is about 1346.0404897328. The cubic root of 1811825 is about 121.9098366335.

The spelling of 1811825 in words is "one million, eight hundred eleven thousand, eight hundred twenty-five".