663835993 has 4 divisors (see below), whose sum is σ = 664206388. Its totient is φ = 663465600.

The previous prime is 663835987. The next prime is 663836023. The reversal of 663835993 is 399538366.

663835993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 439195849 + 224640144 = 20957^2 + 14988^2 .

It is a cyclic number.

It is not a de Polignac number, because 663835993 - 2⁹ = 663835481 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 663835993.

It is not an unprimeable number, because it can be changed into a prime (663835903) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 182496 + ... + 186097.

It is an arithmetic number, because the mean of its divisors is an integer number (166051597).

Almost surely, 2^663835993 is an apocalyptic number.

It is an amenable number.

663835993 is a deficient number, since it is larger than the sum of its proper divisors (370395).

663835993 is a wasteful number, since it uses less digits than its factorization.

663835993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370394.

The product of its digits is 3149280, while the sum is 52.

The square root of 663835993 is about 25765.0149039351. The cubic root of 663835993 is about 872.3423000506.

The spelling of 663835993 in words is "six hundred sixty-three million, eight hundred thirty-five thousand, nine hundred ninety-three".