89309981 has 2 divisors, whose sum is σ = 89309982. Its totient is φ = 89309980.

The previous prime is 89309923. The next prime is 89309999. The reversal of 89309981 is 18990398.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50993881 + 38316100 = 7141^2 + 6190^2 .

It is a cyclic number.

It is not a de Polignac number, because 89309981 - 2¹⁰ = 89308957 is a prime.

It is a super-2 number, since 2×89309981² = 15952545412440722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (89309681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 44654990 + 44654991.

It is an arithmetic number, because the mean of its divisors is an integer number (44654991).

Almost surely, 2^89309981 is an apocalyptic number.

It is an amenable number.

89309981 is a deficient number, since it is larger than the sum of its proper divisors (1).

89309981 is an equidigital number, since it uses as much as digits as its factorization.

89309981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 89309981 is about 9450.3958118166. The cubic root of 89309981 is about 446.9922558036.

The spelling of 89309981 in words is "eighty-nine million, three hundred nine thousand, nine hundred eighty-one".