638025984 has 180 divisors, whose sum is σ = 1969935660. Its totient is φ = 205148160.

The previous prime is 638025979. The next prime is 638025991. The reversal of 638025984 is 489520836.

638025984 is a `hidden beast` number, since 638 + 0 + 2 + 5 + 9 + 8 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 377913600 + 260112384 = 19440^2 + 16128^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 600814 + ... + 601874.

It is an arithmetic number, because the mean of its divisors is an integer number (10944087).

Almost surely, 2^638025984 is an apocalyptic number.

638025984 is a gapful number since it is divisible by the number (64) 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 638025984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (984967830).

638025984 is an abundant number, since it is smaller than the sum of its proper divisors (1331909676).

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

638025984 is a wasteful number, since it uses less digits than its factorization.

638025984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1118 (or 1095 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The square root of 638025984 is about 25259.1762335988. The cubic root of 638025984 is about 860.8869450558.

The spelling of 638025984 in words is "six hundred thirty-eight million, twenty-five thousand, nine hundred eighty-four".