1998384950664 has 160 divisors (see below), whose sum is σ = 5764645022400. Its totient is φ = 646316703360.

The previous prime is 1998384950659. The next prime is 1998384950689. The reversal of 1998384950664 is 4660594838991.

1998384950664 is a `hidden beast` number, since 19 + 9 + 8 + 3 + 8 + 49 + 506 + 64 = 666.

It is a super-2 number, since 2×1998384950664² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 1998384950592 and 1998384950601.

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 39 ways as a sum of consecutive naturals, for example, 8491299 + ... + 8723469.

It is an arithmetic number, because the mean of its divisors is an integer number (36029031390).

Almost surely, 2^{1998384950664} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1998384950664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2882322511200).

1998384950664 is an abundant number, since it is smaller than the sum of its proper divisors (3766260071736).

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

1998384950664 is a wasteful number, since it uses less digits than its factorization.

1998384950664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232585 (or 232572 counting only the distinct ones).

The product of its (nonzero) digits is 403107840, while the sum is 72.

The spelling of 1998384950664 in words is "one trillion, nine hundred ninety-eight billion, three hundred eighty-four million, nine hundred fifty thousand, six hundred sixty-four".