663551994 has 32 divisors (see below), whose sum is σ = 1519902720. Its totient is φ = 189184752.

The previous prime is 663551983. The next prime is 663552011. The reversal of 663551994 is 499155366.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3627 + ... + 36609.

It is an arithmetic number, because the mean of its divisors is an integer number (47496960).

Almost surely, 2^663551994 is an apocalyptic number.

663551994 is an abundant number, since it is smaller than the sum of its proper divisors (856350726).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

663551994 is a wasteful number, since it uses less digits than its factorization.

663551994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33474.

The product of its digits is 874800, while the sum is 48.

The square root of 663551994 is about 25759.5029843357. The cubic root of 663551994 is about 872.2178819305.

The spelling of 663551994 in words is "six hundred sixty-three million, five hundred fifty-one thousand, nine hundred ninety-four".