1638983808 has 320 divisors, whose sum is σ = 6084112320. Its totient is φ = 425502720.

The previous prime is 1638983803. The next prime is 1638983851. The reversal of 1638983808 is 8083898361.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1638983803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 797310 + ... + 799362.

It is an arithmetic number, because the mean of its divisors is an integer number (19012851).

Almost surely, 2^1638983808 is an apocalyptic number.

1638983808 is a gapful number since it is divisible by the number (18) 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 1638983808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3042056160).

1638983808 is an abundant number, since it is smaller than the sum of its proper divisors (4445128512).

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

1638983808 is a wasteful number, since it uses less digits than its factorization.

1638983808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2097 (or 2076 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 54.

The square root of 1638983808 is about 40484.3649820520. The cubic root of 1638983808 is about 1179.0300868339.

The spelling of 1638983808 in words is "one billion, six hundred thirty-eight million, nine hundred eighty-three thousand, eight hundred eight".