1638983098440 has 320 divisors, whose sum is σ = 5546475894960. Its totient is φ = 434079959040.

The previous prime is 1638983098433. The next prime is 1638983098469. The reversal of 1638983098440 is 448903898361.

1638983098440 is a `hidden beast` number, since 16 + 3 + 8 + 98 + 3 + 0 + 98 + 440 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 633523667364 + 1005459431076 = 795942^2 + 1002726^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 640977642 + ... + 640980198.

Almost surely, 2^{1638983098440} is an apocalyptic number.

1638983098440 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 1638983098440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2773237947480).

1638983098440 is an abundant number, since it is smaller than the sum of its proper divisors (3907492796520).

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

1638983098440 is a wasteful number, since it uses less digits than its factorization.

1638983098440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3854 (or 3841 counting only the distinct ones).

The product of its (nonzero) digits is 35831808, while the sum is 63.

The spelling of 1638983098440 in words is "one trillion, six hundred thirty-eight billion, nine hundred eighty-three million, ninety-eight thousand, four hundred forty".