999982000081 has 27 divisors (see below), whose sum is σ = 1081659174609. Its totient is φ = 924279681408.

The previous prime is 999982000067. The next prime is 999982000139. The reversal of 999982000081 is 180000289999.

The square root of 999982000081 is 999991.

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

It can be written as a sum of positive squares in 4 ways, for example, as 413501727681 + 586480272400 = 643041^2 + 765820^2 .

It is not a de Polignac number, because 999982000081 - 2¹⁹ = 999981475793 is a prime.

It is a super-2 number, since 2×999982000081² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 999981999986 and 999982000031.

It is not an unprimeable number, because it can be changed into a prime (999982000051) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1002990475 + ... + 1002991471.

Almost surely, 2^999982000081 is an apocalyptic number.

999982000081 is the 999991-st square number.

999982000081 is the 499996-th centered octagonal number.

It is an amenable number.

999982000081 is a deficient number, since it is larger than the sum of its proper divisors (81677174528).

999982000081 is an frugal number, since it uses more digits than its factorization.

999982000081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2146 (or 1073 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 55.

The spelling of 999982000081 in words is "nine hundred ninety-nine billion, nine hundred eighty-two million, eighty-one", and thus it is an aban number.