1998061406784 has 63 divisors (see below), whose sum is σ = 5727179502057. Its totient is φ = 666009160704.

The previous prime is 1998061406779. The next prime is 1998061406801. The reversal of 1998061406784 is 4876041608991.

The square root of 1998061406784 is 1413528.

It is a perfect power (a square), and thus also a powerful number.

1998061406784 is a `hidden beast` number, since 1 + 9 + 9 + 8 + 0 + 614 + 0 + 6 + 7 + 8 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 276381518400 + 1721679888384 = 525720^2 + 1312128^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 33895224 + ... + 33954120.

Almost surely, 2^{1998061406784} is an apocalyptic number.

1998061406784 is the 1413528-th square number.

It is an amenable number.

1998061406784 is an abundant number, since it is smaller than the sum of its proper divisors (3729118095273).

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

1998061406784 is an frugal number, since it uses more digits than its factorization.

1998061406784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117812 (or 58902 counting only the distinct ones).

The product of its (nonzero) digits is 20901888, while the sum is 63.

The spelling of 1998061406784 in words is "one trillion, nine hundred ninety-eight billion, sixty-one million, four hundred six thousand, seven hundred eighty-four".