638539232760 has 768 divisors, whose sum is σ = 2572891776000. Its totient is φ = 135026196480.

The previous prime is 638539232731. The next prime is 638539232803. The reversal of 638539232760 is 67232935836.

It is a happy number.

638539232760 is a `hidden beast` number, since 6 + 3 + 8 + 539 + 2 + 32 + 76 + 0 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 638539232697 and 638539232706.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 632843136 + ... + 632844144.

It is an arithmetic number, because the mean of its divisors is an integer number (3350119500).

Almost surely, 2^638539232760 is an apocalyptic number.

638539232760 is a gapful number since it is divisible by the number (60) 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 638539232760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1286445888000).

638539232760 is an abundant number, since it is smaller than the sum of its proper divisors (1934352543240).

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

638539232760 is a wasteful number, since it uses less digits than its factorization.

638539232760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1716 (or 1709 counting only the distinct ones).

The product of its (nonzero) digits is 9797760, while the sum is 54.

The spelling of 638539232760 in words is "six hundred thirty-eight billion, five hundred thirty-nine million, two hundred thirty-two thousand, seven hundred sixty".