663689629 has 2 divisors, whose sum is σ = 663689630. Its totient is φ = 663689628.

The previous prime is 663689597. The next prime is 663689641. The reversal of 663689629 is 926986366.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 344102500 + 319587129 = 18550^2 + 17877^2 .

It is a cyclic number.

It is not a de Polignac number, because 663689629 - 2⁵ = 663689597 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 663689629.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (663689729) 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, 331844814 + 331844815.

It is an arithmetic number, because the mean of its divisors is an integer number (331844815).

Almost surely, 2^663689629 is an apocalyptic number.

It is an amenable number.

663689629 is a deficient number, since it is larger than the sum of its proper divisors (1).

663689629 is an equidigital number, since it uses as much as digits as its factorization.

663689629 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5038848, while the sum is 55.

The square root of 663689629 is about 25762.1743841625. The cubic root of 663689629 is about 872.2781833638.

The spelling of 663689629 in words is "six hundred sixty-three million, six hundred eighty-nine thousand, six hundred twenty-nine".