663617720 has 16 divisors (see below), whose sum is σ = 1493139960. Its totient is φ = 265447072.

The previous prime is 663617711. The next prime is 663617723. The reversal of 663617720 is 27716366.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (663617723) 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, 8295182 + ... + 8295261.

Almost surely, 2^663617720 is an apocalyptic number.

It is an amenable number.

663617720 is an abundant number, since it is smaller than the sum of its proper divisors (829522240).

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

663617720 is a wasteful number, since it uses less digits than its factorization.

663617720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16590454 (or 16590450 counting only the distinct ones).

The product of its (nonzero) digits is 63504, while the sum is 38.

The square root of 663617720 is about 25760.7787149379. The cubic root of 663617720 is about 872.2466792216.

The spelling of 663617720 in words is "six hundred sixty-three million, six hundred seventeen thousand, seven hundred twenty".