8987117989 has 2 divisors, whose sum is σ = 8987117990. Its totient is φ = 8987117988.

The previous prime is 8987117941. The next prime is 8987118029. The reversal of 8987117989 is 9897117898.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5383156900 + 3603961089 = 73370^2 + 60033^2 .

It is a cyclic number.

It is not a de Polignac number, because 8987117989 - 2¹⁵ = 8987085221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8987117929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4493558994 + 4493558995.

It is an arithmetic number, because the mean of its divisors is an integer number (4493558995).

Almost surely, 2^8987117989 is an apocalyptic number.

It is an amenable number.

8987117989 is a deficient number, since it is larger than the sum of its proper divisors (1).

8987117989 is an equidigital number, since it uses as much as digits as its factorization.

8987117989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18289152, while the sum is 67.

The square root of 8987117989 is about 94800.4113334958. The cubic root of 8987117989 is about 2079.0909172228.

Subtracting 8987117989 from its reverse (9897117898), we obtain a palindrome (909999909).

The spelling of 8987117989 in words is "eight billion, nine hundred eighty-seven million, one hundred seventeen thousand, nine hundred eighty-nine".