663461321 has 2 divisors, whose sum is σ = 663461322. Its totient is φ = 663461320.

The previous prime is 663461297. The next prime is 663461347. The reversal of 663461321 is 123164366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 605701321 + 57760000 = 24611^2 + 7600^2 .

It is a cyclic number.

It is not a de Polignac number, because 663461321 - 2⁶ = 663461257 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (663161321) 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 as a sum of consecutive naturals, namely, 331730660 + 331730661.

It is an arithmetic number, because the mean of its divisors is an integer number (331730661).

Almost surely, 2^663461321 is an apocalyptic number.

It is an amenable number.

663461321 is a deficient number, since it is larger than the sum of its proper divisors (1).

663461321 is an equidigital number, since it uses as much as digits as its factorization.

663461321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 32.

The square root of 663461321 is about 25757.7429329512. The cubic root of 663461321 is about 872.1781512009.

The spelling of 663461321 in words is "six hundred sixty-three million, four hundred sixty-one thousand, three hundred twenty-one".