638891848 has 64 divisors (see below), whose sum is σ = 1407813120. Its totient is φ = 266112000.

The previous prime is 638891843. The next prime is 638891849. The reversal of 638891848 is 848198836.

It is not an unprimeable number, because it can be changed into a prime (638891843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1062748 + ... + 1063348.

It is an arithmetic number, because the mean of its divisors is an integer number (21997080).

Almost surely, 2^638891848 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638891848, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (703906560).

638891848 is an abundant number, since it is smaller than the sum of its proper divisors (768921272).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

638891848 is a wasteful number, since it uses less digits than its factorization.

638891848 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1118 (or 1114 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 55.

The square root of 638891848 is about 25276.3100155066. The cubic root of 638891848 is about 861.2762051004.

The spelling of 638891848 in words is "six hundred thirty-eight million, eight hundred ninety-one thousand, eight hundred forty-eight".