638631464136836 has 24 divisors (see below), whose sum is σ = 1162463379221760. Its totient is φ = 306656329730400.

The previous prime is 638631464136797. The next prime is 638631464136857.

638631464136836 is nontrivially palindromic in base 10.

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, 19657440791 + ... + 19657473278.

It is an arithmetic number, because the mean of its divisors is an integer number (48435974134240).

Almost surely, 2^{638631464136836} is an apocalyptic number.

It is an amenable number.

638631464136836 is a deficient number, since it is larger than the sum of its proper divisors (523831915084924).

638631464136836 is a wasteful number, since it uses less digits than its factorization.

638631464136836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39314914235 (or 39314914233 counting only the distinct ones).

The product of its digits is 644972544, while the sum is 68.

The spelling of 638631464136836 in words is "six hundred thirty-eight trillion, six hundred thirty-one billion, four hundred sixty-four million, one hundred thirty-six thousand, eight hundred thirty-six".