663551998 has 8 divisors (see below), whose sum is σ = 995672808. Its totient is φ = 331661064.

The previous prime is 663551983. The next prime is 663552011. The reversal of 663551998 is 899155366.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50061 + ... + 61912.

It is an arithmetic number, because the mean of its divisors is an integer number (124459101).

Almost surely, 2^663551998 is an apocalyptic number.

663551998 is a deficient number, since it is larger than the sum of its proper divisors (332120810).

663551998 is a wasteful number, since it uses less digits than its factorization.

663551998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114938.

The product of its digits is 1749600, while the sum is 52.

The square root of 663551998 is about 25759.5030619770. The cubic root of 663551998 is about 872.2178836831.

The spelling of 663551998 in words is "six hundred sixty-three million, five hundred fifty-one thousand, nine hundred ninety-eight".