638285812 has 6 divisors (see below), whose sum is σ = 1117000178. Its totient is φ = 319142904.

The previous prime is 638285807. The next prime is 638285819. The reversal of 638285812 is 218582836.

It can be written as a sum of positive squares in only one way, i.e., 451307536 + 186978276 = 21244^2 + 13674^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638285819) 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 as a sum of consecutive naturals, namely, 79785723 + ... + 79785730.

Almost surely, 2^638285812 is an apocalyptic number.

It is an amenable number.

638285812 is a deficient number, since it is larger than the sum of its proper divisors (478714366).

638285812 is a wasteful number, since it uses less digits than its factorization.

638285812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159571457 (or 159571455 counting only the distinct ones).

The product of its digits is 184320, while the sum is 43.

The square root of 638285812 is about 25264.3189498550. The cubic root of 638285812 is about 861.0037909636.

The spelling of 638285812 in words is "six hundred thirty-eight million, two hundred eighty-five thousand, eight hundred twelve".