663645242 has 16 divisors (see below), whose sum is σ = 1073225832. Its totient is φ = 305959680.

The previous prime is 663645233. The next prime is 663645313. The reversal of 663645242 is 242546366.

It can be written as a sum of positive squares in 4 ways, for example, as 513067801 + 150577441 = 22651^2 + 12271^2 .

It is a junction number, because it is equal to n+sod(n) for n = 663645196 and 663645205.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10742 + ... + 37982.

Almost surely, 2^663645242 is an apocalyptic number.

663645242 is a deficient number, since it is larger than the sum of its proper divisors (409580590).

663645242 is a wasteful number, since it uses less digits than its factorization.

663645242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28193.

The product of its digits is 207360, while the sum is 38.

The square root of 663645242 is about 25761.3128935619. The cubic root of 663645242 is about 872.2587371884.

The spelling of 663645242 in words is "six hundred sixty-three million, six hundred forty-five thousand, two hundred forty-two".