638801100 has 288 divisors, whose sum is σ = 2384291840. Its totient is φ = 143700480.

The previous prime is 638801099. The next prime is 638801123. The reversal of 638801100 is 1108836.

It is a super-2 number, since 2×638801100² = 816133690722420000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 1379469 + ... + 1379931.

Almost surely, 2^638801100 is an apocalyptic number.

638801100 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638801100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1192145920).

638801100 is an abundant number, since it is smaller than the sum of its proper divisors (1745490740).

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

638801100 is a wasteful number, since it uses less digits than its factorization.

638801100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566 (or 553 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 638801100 is about 25274.5148321387. The cubic root of 638801100 is about 861.2354247012.

Adding to 638801100 its reverse (1108836), we get a palindrome (639909936).

It can be divided in two parts, 63880 and 1100, that added together give a triangular number (64980 = T₃₆₀).

The spelling of 638801100 in words is "six hundred thirty-eight million, eight hundred one thousand, one hundred".