638059968 has 504 divisors, whose sum is σ = 2403116352. Its totient is φ = 160247808.

The previous prime is 638059909. The next prime is 638059969. The reversal of 638059968 is 869950836.

It is a tau number, because it is divible by the number of its divisors (504).

It is a super-2 number, since 2×638059968² = 814241045528322048, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638059969) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 13575721 + ... + 13575767.

It is an arithmetic number, because the mean of its divisors is an integer number (4768088).

Almost surely, 2^638059968 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 638059968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1201558176).

638059968 is an abundant number, since it is smaller than the sum of its proper divisors (1765056384).

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

638059968 is a wasteful number, since it uses less digits than its factorization.

638059968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 109 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 54.

The square root of 638059968 is about 25259.8489306646. The cubic root of 638059968 is about 860.9022296279.

The spelling of 638059968 in words is "six hundred thirty-eight million, fifty-nine thousand, nine hundred sixty-eight".