663440331 has 32 divisors (see below), whose sum is σ = 939939840. Its totient is φ = 415641600.

The previous prime is 663440321. The next prime is 663440353. The reversal of 663440331 is 133044366.

It is not a de Polignac number, because 663440331 - 2⁵ = 663440299 is a prime.

It is a super-2 number, since 2×663440331² = 880306145594779122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (663440321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 470155 + ... + 471563.

It is an arithmetic number, because the mean of its divisors is an integer number (29373120).

Almost surely, 2^663440331 is an apocalyptic number.

663440331 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

663440331 is a deficient number, since it is larger than the sum of its proper divisors (276499509).

663440331 is a wasteful number, since it uses less digits than its factorization.

663440331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1587.

The product of its (nonzero) digits is 15552, while the sum is 30.

The square root of 663440331 is about 25757.3354794319. The cubic root of 663440331 is about 872.1689533713.

Adding to 663440331 its reverse (133044366), we get a palindrome (796484697).

The spelling of 663440331 in words is "six hundred sixty-three million, four hundred forty thousand, three hundred thirty-one".