1638134860 has 48 divisors (see below), whose sum is σ = 3573884160. Its totient is φ = 630040320.

The previous prime is 1638134821. The next prime is 1638134867. The reversal of 1638134860 is 684318361.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (1638134867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88926 + ... + 105754.

It is an arithmetic number, because the mean of its divisors is an integer number (74455920).

Almost surely, 2^1638134860 is an apocalyptic number.

1638134860 is a gapful number since it is divisible by the number (10) 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 1638134860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1786942080).

1638134860 is an abundant number, since it is smaller than the sum of its proper divisors (1935749300).

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

1638134860 is a wasteful number, since it uses less digits than its factorization.

1638134860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17026 (or 17024 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 40.

The square root of 1638134860 is about 40473.8787367853. The cubic root of 1638134860 is about 1178.8264834186.

The spelling of 1638134860 in words is "one billion, six hundred thirty-eight million, one hundred thirty-four thousand, eight hundred sixty".