638863637546 has 8 divisors (see below), whose sum is σ = 974005218084. Its totient is φ = 314195231520.

The previous prime is 638863637543. The next prime is 638863637593. The reversal of 638863637546 is 645736368836.

It can be written as a sum of positive squares in 2 ways, for example, as 588348827521 + 50514810025 = 767039^2 + 224755^2 .

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

It is not an unprimeable number, because it can be changed into a prime (638863637543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2618293475 + ... + 2618293718.

Almost surely, 2^638863637546 is an apocalyptic number.

638863637546 is a deficient number, since it is larger than the sum of its proper divisors (335141580538).

638863637546 is a wasteful number, since it uses less digits than its factorization.

638863637546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5236587256.

The product of its digits is 313528320, while the sum is 65.

The spelling of 638863637546 in words is "six hundred thirty-eight billion, eight hundred sixty-three million, six hundred thirty-seven thousand, five hundred forty-six".