663979501 has 2 divisors, whose sum is σ = 663979502. Its totient is φ = 663979500.

The previous prime is 663979471. The next prime is 663979517. The reversal of 663979501 is 105979366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 355134025 + 308845476 = 18845^2 + 17574^2 .

It is a cyclic number.

It is not a de Polignac number, because 663979501 - 2⁷ = 663979373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (663979201) 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, 331989750 + 331989751.

It is an arithmetic number, because the mean of its divisors is an integer number (331989751).

Almost surely, 2^663979501 is an apocalyptic number.

It is an amenable number.

663979501 is a deficient number, since it is larger than the sum of its proper divisors (1).

663979501 is an equidigital number, since it uses as much as digits as its factorization.

663979501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 306180, while the sum is 46.

The square root of 663979501 is about 25767.7996926396. The cubic root of 663979501 is about 872.4051564790.

The spelling of 663979501 in words is "six hundred sixty-three million, nine hundred seventy-nine thousand, five hundred one".