638866634452 has 192 divisors, whose sum is σ = 1265833820160. Its totient is φ = 280934438400.

The previous prime is 638866634443. The next prime is 638866634453. The reversal of 638866634452 is 254436668836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638866634453) 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 63 ways as a sum of consecutive naturals, for example, 966515002 + ... + 966515662.

It is an arithmetic number, because the mean of its divisors is an integer number (6592884480).

Almost surely, 2^638866634452 is an apocalyptic number.

It is an amenable number.

638866634452 is a deficient number, since it is larger than the sum of its proper divisors (626967185708).

638866634452 is a wasteful number, since it uses less digits than its factorization.

638866634452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 942 (or 940 counting only the distinct ones).

The product of its digits is 119439360, while the sum is 61.

The spelling of 638866634452 in words is "six hundred thirty-eight billion, eight hundred sixty-six million, six hundred thirty-four thousand, four hundred fifty-two".