638355384580 has 192 divisors, whose sum is σ = 1578193182720. Its totient is φ = 215202355200.

The previous prime is 638355384533. The next prime is 638355384581. The reversal of 638355384580 is 85483553836.

It is not an unprimeable number, because it can be changed into a prime (638355384581) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8574115 + ... + 8648245.

It is an arithmetic number, because the mean of its divisors is an integer number (8219756160).

Almost surely, 2^638355384580 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 638355384580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (789096591360).

638355384580 is an abundant number, since it is smaller than the sum of its proper divisors (939837798140).

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

638355384580 is a wasteful number, since it uses less digits than its factorization.

638355384580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74250 (or 74248 counting only the distinct ones).

The product of its (nonzero) digits is 41472000, while the sum is 58.

The spelling of 638355384580 in words is "six hundred thirty-eight billion, three hundred fifty-five million, three hundred eighty-four thousand, five hundred eighty".