663969001 has 4 divisors (see below), whose sum is σ = 676496772. Its totient is φ = 651441232.

The previous prime is 663968971. The next prime is 663969029. The reversal of 663969001 is 100969366.

It is a happy number.

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 210279001 + 453690000 = 14501^2 + 21300^2 .

It is not a de Polignac number, because 663969001 - 2⁵ = 663968969 is a prime.

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 Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (663969071) 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 in 3 ways as a sum of consecutive naturals, for example, 6263806 + ... + 6263911.

It is an arithmetic number, because the mean of its divisors is an integer number (169124193).

Almost surely, 2^663969001 is an apocalyptic number.

It is an amenable number.

663969001 is a deficient number, since it is larger than the sum of its proper divisors (12527771).

663969001 is a wasteful number, since it uses less digits than its factorization.

663969001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12527770.

The product of its (nonzero) digits is 52488, while the sum is 40.

The square root of 663969001 is about 25767.5959491762. The cubic root of 663969001 is about 872.4005577917.

The spelling of 663969001 in words is "six hundred sixty-three million, nine hundred sixty-nine thousand, one".