9888888881 has 2 divisors, whose sum is σ = 9888888882. Its totient is φ = 9888888880.

The previous prime is 9888888871. The next prime is 9888888887. The reversal of 9888888881 is 1888888889.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6952224400 + 2936664481 = 83380^2 + 54191^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9888888881 is a prime.

It is a super-2 number, since 2×9888888881² (a number of 21 digits) contains 22 as substring.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 9888888799 and 9888888808.

It is not a weakly prime, because it can be changed into another prime (9888888887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4944444440 + 4944444441.

It is an arithmetic number, because the mean of its divisors is an integer number (4944444441).

Almost surely, 2^9888888881 is an apocalyptic number.

It is an amenable number.

9888888881 is a deficient number, since it is larger than the sum of its proper divisors (1).

9888888881 is an equidigital number, since it uses as much as digits as its factorization.

9888888881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 150994944, while the sum is 74.

The square root of 9888888881 is about 99442.8925615099. The cubic root of 9888888881 is about 2146.4255646422.

It can be divided in two parts, 988888888 and 1, that added together give a palindrome (988888889).

The spelling of 9888888881 in words is "nine billion, eight hundred eighty-eight million, eight hundred eighty-eight thousand, eight hundred eighty-one".