663229961 has 2 divisors, whose sum is σ = 663229962. Its totient is φ = 663229960.

The previous prime is 663229949. The next prime is 663229999. The reversal of 663229961 is 169922366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 627001600 + 36228361 = 25040^2 + 6019^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-663229961 is a prime.

It is not a weakly prime, because it can be changed into another prime (663229261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331614980 + 331614981.

It is an arithmetic number, because the mean of its divisors is an integer number (331614981).

Almost surely, 2^663229961 is an apocalyptic number.

It is an amenable number.

663229961 is a deficient number, since it is larger than the sum of its proper divisors (1).

663229961 is an equidigital number, since it uses as much as digits as its factorization.

663229961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 209952, while the sum is 44.

The square root of 663229961 is about 25753.2514646209. The cubic root of 663229961 is about 872.0767584039.

The spelling of 663229961 in words is "six hundred sixty-three million, two hundred twenty-nine thousand, nine hundred sixty-one".