638762400 has 216 divisors, whose sum is σ = 2282978880. Its totient is φ = 168030720.

The previous prime is 638762393. The next prime is 638762401. The reversal of 638762400 is 4267836.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (638762401) 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 35 ways as a sum of consecutive naturals, for example, 568239 + ... + 569361.

Almost surely, 2^638762400 is an apocalyptic number.

638762400 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 638762400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1141489440).

638762400 is an abundant number, since it is smaller than the sum of its proper divisors (1644216480).

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

638762400 is a wasteful number, since it uses less digits than its factorization.

638762400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1228 (or 1212 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 638762400 is about 25273.7492272120. The cubic root of 638762400 is about 861.2180324936.

The spelling of 638762400 in words is "six hundred thirty-eight million, seven hundred sixty-two thousand, four hundred".