989929988 has 6 divisors (see below), whose sum is σ = 1732377486. Its totient is φ = 494964992.

The previous prime is 989929981. The next prime is 989929999. The reversal of 989929988 is 889929989.

It can be written as a sum of positive squares in only one way, i.e., 909504964 + 80425024 = 30158^2 + 8968^2 .

It is a super-2 number, since 2×989929988² = 1959922762283360288, which contains 22 as substring.

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 as a sum of consecutive naturals, namely, 123741245 + ... + 123741252.

It is an arithmetic number, because the mean of its divisors is an integer number (288729581).

Almost surely, 2^989929988 is an apocalyptic number.

It is an amenable number.

989929988 is a deficient number, since it is larger than the sum of its proper divisors (742447498).

989929988 is a wasteful number, since it uses less digits than its factorization.

989929988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247482501 (or 247482499 counting only the distinct ones).

The product of its digits is 60466176, while the sum is 71.

The square root of 989929988 is about 31463.1528617206. The cubic root of 989929988 is about 996.6319986350.

Subtracting from 989929988 its reverse (889929989), we obtain a palindrome (99999999).

The spelling of 989929988 in words is "nine hundred eighty-nine million, nine hundred twenty-nine thousand, nine hundred eighty-eight".