638754816 has 224 divisors, whose sum is σ = 2013143040. Its totient is φ = 176357376.

The previous prime is 638754799. The next prime is 638754881. The reversal of 638754816 is 618457836.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8085465 + ... + 8085543.

Almost surely, 2^638754816 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 638754816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1006571520).

638754816 is an abundant number, since it is smaller than the sum of its proper divisors (1374388224).

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

638754816 is an equidigital number, since it uses as much as digits as its factorization.

638754816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162 (or 138 counting only the distinct ones).

The product of its digits is 967680, while the sum is 48.

The square root of 638754816 is about 25273.5991896683. The cubic root of 638754816 is about 861.2146240779.

The spelling of 638754816 in words is "six hundred thirty-eight million, seven hundred fifty-four thousand, eight hundred sixteen".