638734041330 has 384 divisors, whose sum is σ = 2005159242240. Its totient is φ = 127307980800.

The previous prime is 638734041317. The next prime is 638734041331. The reversal of 638734041330 is 33140437836.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (638734041331) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 115688970 + ... + 115694490.

It is an arithmetic number, because the mean of its divisors is an integer number (5221768860).

Almost surely, 2^638734041330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638734041330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1002579621120).

638734041330 is an abundant number, since it is smaller than the sum of its proper divisors (1366425200910).

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

638734041330 is a wasteful number, since it uses less digits than its factorization.

638734041330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5746 (or 5735 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 42.

The spelling of 638734041330 in words is "six hundred thirty-eight billion, seven hundred thirty-four million, forty-one thousand, three hundred thirty".