1984827327921 has 9 divisors (see below), whose sum is σ = 2866978911979. Its totient is φ = 1323215400936.

The previous prime is 1984827327919. The next prime is 1984827327929. The reversal of 1984827327921 is 1297237284891.

The square root of 1984827327921 is 1408839.

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

1984827327921 is a `hidden beast` number, since 1 + 98 + 4 + 8 + 273 + 279 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1909661429025 + 75165898896 = 1381905^2 + 274164^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 1984827327921 - 2¹ = 1984827327919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1984827327929) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3991711 + ... + 4461323.

Almost surely, 2^{1984827327921} is an apocalyptic number.

1984827327921 is the 1408839-th square number.

1984827327921 is the 704420-th centered octagonal number.

It is an amenable number.

1984827327921 is a deficient number, since it is larger than the sum of its proper divisors (882151584058).

1984827327921 is an frugal number, since it uses more digits than its factorization.

1984827327921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 939232 (or 469616 counting only the distinct ones).

The product of its digits is 24385536, while the sum is 63.

The spelling of 1984827327921 in words is "one trillion, nine hundred eighty-four billion, eight hundred twenty-seven million, three hundred twenty-seven thousand, nine hundred twenty-one".