663838825 has 12 divisors (see below), whose sum is σ = 886480588. Its totient is φ = 490219200.

The previous prime is 663838823. The next prime is 663838829. The reversal of 663838825 is 528838366.

It can be written as a sum of positive squares in 6 ways, for example, as 169754841 + 494083984 = 13029^2 + 22228^2 .

It is not a de Polignac number, because 663838825 - 2¹ = 663838823 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (663838823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1020966 + ... + 1021615.

Almost surely, 2^663838825 is an apocalyptic number.

663838825 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

663838825 is a deficient number, since it is larger than the sum of its proper divisors (222641763).

663838825 is a wasteful number, since it uses less digits than its factorization.

663838825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2042604 (or 2042599 counting only the distinct ones).

The product of its digits is 1658880, while the sum is 49.

The square root of 663838825 is about 25765.0698621215. The cubic root of 663838825 is about 872.3435405527.

The spelling of 663838825 in words is "six hundred sixty-three million, eight hundred thirty-eight thousand, eight hundred twenty-five".