663181366 has 4 divisors (see below), whose sum is σ = 994772052. Its totient is φ = 331590682.

The previous prime is 663181349. The next prime is 663181381.

663181366 is nontrivially palindromic in base 10.

663181366 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 is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 165795340 + ... + 165795343.

It is an arithmetic number, because the mean of its divisors is an integer number (248693013).

Almost surely, 2^663181366 is an apocalyptic number.

663181366 is a deficient number, since it is larger than the sum of its proper divisors (331590686).

663181366 is a wasteful number, since it uses less digits than its factorization.

663181366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331590685.

The product of its digits is 93312, while the sum is 40.

The square root of 663181366 is about 25752.3079742380. The cubic root of 663181366 is about 872.0554588006.

The spelling of 663181366 in words is "six hundred sixty-three million, one hundred eighty-one thousand, three hundred sixty-six".