9782897981 has 2 divisors, whose sum is σ = 9782897982. Its totient is φ = 9782897980.

The previous prime is 9782897963. The next prime is 9782897983. The reversal of 9782897981 is 1897982879.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7614133081 + 2168764900 = 87259^2 + 46570^2 .

It is a cyclic number.

It is not a de Polignac number, because 9782897981 - 2¹⁴ = 9782881597 is a prime.

It is a super-2 number, since 2×9782897981² (a number of 21 digits) contains 22 as substring.

Together with 9782897983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9782897983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4891448990 + 4891448991.

It is an arithmetic number, because the mean of its divisors is an integer number (4891448991).

Almost surely, 2^9782897981 is an apocalyptic number.

It is an amenable number.

9782897981 is a deficient number, since it is larger than the sum of its proper divisors (1).

9782897981 is an equidigital number, since it uses as much as digits as its factorization.

9782897981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36578304, while the sum is 68.

The square root of 9782897981 is about 98908.5334083971. The cubic root of 9782897981 is about 2138.7294100366.

The spelling of 9782897981 in words is "nine billion, seven hundred eighty-two million, eight hundred ninety-seven thousand, nine hundred eighty-one".