989929989 has 6 divisors (see below), whose sum is σ = 1429898886. Its totient is φ = 659953320.

The previous prime is 989929981. The next prime is 989929999.

989929989 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in only one way, i.e., 897481764 + 92448225 = 29958^2 + 9615^2 .

It is not a de Polignac number, because 989929989 - 2³ = 989929981 is a prime.

It is a super-2 number, since 2×989929989² = 1959922766243080242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (989929981) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 54996102 + ... + 54996119.

It is an arithmetic number, because the mean of its divisors is an integer number (238316481).

Almost surely, 2^989929989 is an apocalyptic number.

It is an amenable number.

989929989 is a deficient number, since it is larger than the sum of its proper divisors (439968897).

989929989 is a wasteful number, since it uses less digits than its factorization.

989929989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109992227 (or 109992224 counting only the distinct ones).

The product of its digits is 68024448, while the sum is 72.

The square root of 989929989 is about 31463.1528776122. The cubic root of 989929989 is about 996.6319989706.

The spelling of 989929989 in words is "nine hundred eighty-nine million, nine hundred twenty-nine thousand, nine hundred eighty-nine".