1638384384 has 432 divisors, whose sum is σ = 5813283168. Its totient is φ = 404619264.

The previous prime is 1638384353. The next prime is 1638384413. The reversal of 1638384384 is 4834838361.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8316574 + ... + 8316770.

It is an arithmetic number, because the mean of its divisors is an integer number (13456674).

Almost surely, 2^1638384384 is an apocalyptic number.

1638384384 is a gapful number since it is divisible by the number (14) 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 1638384384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2906641584).

1638384384 is an abundant number, since it is smaller than the sum of its proper divisors (4174898784).

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

1638384384 is a wasteful number, since it uses less digits than its factorization.

1638384384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260 (or 239 counting only the distinct ones).

The product of its digits is 1327104, while the sum is 48.

The square root of 1638384384 is about 40476.9611507583. The cubic root of 1638384384 is about 1178.8863341210.

The spelling of 1638384384 in words is "one billion, six hundred thirty-eight million, three hundred eighty-four thousand, three hundred eighty-four".