1821725 has 6 divisors (see below), whose sum is σ = 2258970. Its totient is φ = 1457360.

The previous prime is 1821713. The next prime is 1821731. The reversal of 1821725 is 5271281.

It can be written as a sum of positive squares in 3 ways, for example, as 276676 + 1545049 = 526^2 + 1243^2 .

It is not a de Polignac number, because 1821725 - 2⁴ = 1821709 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1821694 and 1821703.

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, 36410 + ... + 36459.

It is an arithmetic number, because the mean of its divisors is an integer number (376495).

2^1821725 is an apocalyptic number.

It is an amenable number.

1821725 is a deficient number, since it is larger than the sum of its proper divisors (437245).

1821725 is an equidigital number, since it uses as much as digits as its factorization.

1821725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72879 (or 72874 counting only the distinct ones).

The product of its digits is 1120, while the sum is 26.

The square root of 1821725 is about 1349.7129324416. The cubic root of 1821725 is about 122.1314761055.

The spelling of 1821725 in words is "one million, eight hundred twenty-one thousand, seven hundred twenty-five".