2181825 has 18 divisors (see below), whose sum is σ = 3908294. Its totient is φ = 1163520.

The previous prime is 2181737. The next prime is 2181833. The reversal of 2181825 is 5281812.

It can be written as a sum of positive squares in 3 ways, for example, as 3249 + 2178576 = 57^2 + 1476^2 .

It is not a de Polignac number, because 2181825 - 2¹¹ = 2179777 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4624 + ... + 5073.

2^2181825 is an apocalyptic number.

2181825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2181825 is a deficient number, since it is larger than the sum of its proper divisors (1726469).

2181825 is a wasteful number, since it uses less digits than its factorization.

2181825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9713 (or 9705 counting only the distinct ones).

The product of its digits is 1280, while the sum is 27.

The square root of 2181825 is about 1477.1001997156. The cubic root of 2181825 is about 129.6999985535.

The spelling of 2181825 in words is "two million, one hundred eighty-one thousand, eight hundred twenty-five".