1663225 has 6 divisors (see below), whose sum is σ = 2062430. Its totient is φ = 1330560.

The previous prime is 1663223. The next prime is 1663267. The reversal of 1663225 is 5223661.

It can be written as a sum of positive squares in 3 ways, for example, as 287296 + 1375929 = 536^2 + 1173^2 .

It is not a de Polignac number, because 1663225 - 2¹ = 1663223 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: 66529 = 1663225 / (1 + 6 + 6 + 3 + 2 + 2 + 5).

It is a d-powerful number, because it can be written as 1 + 6³ + 6⁶ + 3¹¹ + 2² + 2²⁰ + 5⁸ .

1663225 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1663225.

It is not an unprimeable number, because it can be changed into a prime (1663223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 33240 + ... + 33289.

2^1663225 is an apocalyptic number.

It is an amenable number.

1663225 is a deficient number, since it is larger than the sum of its proper divisors (399205).

1663225 is an equidigital number, since it uses as much as digits as its factorization.

1663225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66539 (or 66534 counting only the distinct ones).

The product of its digits is 2160, while the sum is 25.

The square root of 1663225 is about 1289.6608081197. The cubic root of 1663225 is about 118.4814429688.

Adding to 1663225 its reverse (5223661), we get a palindrome (6886886).

The spelling of 1663225 in words is "one million, six hundred sixty-three thousand, two hundred twenty-five".