663641729 has 2 divisors, whose sum is σ = 663641730. Its totient is φ = 663641728.

The previous prime is 663641723. The next prime is 663641773. The reversal of 663641729 is 927146366.

663641729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (663641773) can be obtained adding 663641729 to its sum of digits (44).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 366148225 + 297493504 = 19135^2 + 17248^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-663641729 is a prime.

It is a super-3 number, since 3×663641729³ (a number of 27 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 663641729.

It is not a weakly prime, because it can be changed into another prime (663641723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331820864 + 331820865.

It is an arithmetic number, because the mean of its divisors is an integer number (331820865).

Almost surely, 2^663641729 is an apocalyptic number.

It is an amenable number.

663641729 is a deficient number, since it is larger than the sum of its proper divisors (1).

663641729 is an equidigital number, since it uses as much as digits as its factorization.

663641729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 326592, while the sum is 44.

The square root of 663641729 is about 25761.2447098350. The cubic root of 663641729 is about 872.2571980878.

The spelling of 663641729 in words is "six hundred sixty-three million, six hundred forty-one thousand, seven hundred twenty-nine".