7989055487981 has 2 divisors, whose sum is σ = 7989055487982. Its totient is φ = 7989055487980.

The previous prime is 7989055487927. The next prime is 7989055488031. The reversal of 7989055487981 is 1897845509897.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7594935203881 + 394120284100 = 2755891^2 + 627790^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7989055487981 is a prime.

It is a super-2 number, since 2×7989055487981² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7989055487896 and 7989055487905.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7989055487911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3994527743990 + 3994527743991.

It is an arithmetic number, because the mean of its divisors is an integer number (3994527743991).

Almost surely, 2^{7989055487981} is an apocalyptic number.

It is an amenable number.

7989055487981 is a deficient number, since it is larger than the sum of its proper divisors (1).

7989055487981 is an equidigital number, since it uses as much as digits as its factorization.

7989055487981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1828915200, while the sum is 80.

The spelling of 7989055487981 in words is "seven trillion, nine hundred eighty-nine billion, fifty-five million, four hundred eighty-seven thousand, nine hundred eighty-one".