988189991 has 8 divisors (see below), whose sum is σ = 1047265920. Its totient is φ = 929219328.

The previous prime is 988189987. The next prime is 988190029. The reversal of 988189991 is 199981889.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 988189991 - 2² = 988189987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (988189091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6551 + ... + 44936.

It is an arithmetic number, because the mean of its divisors is an integer number (130908240).

Almost surely, 2^988189991 is an apocalyptic number.

988189991 is a deficient number, since it is larger than the sum of its proper divisors (59075929).

988189991 is a wasteful number, since it uses less digits than its factorization.

988189991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52633.

The product of its digits is 3359232, while the sum is 62.

The square root of 988189991 is about 31435.4893551858. The cubic root of 988189991 is about 996.0477304777.

The spelling of 988189991 in words is "nine hundred eighty-eight million, one hundred eighty-nine thousand, nine hundred ninety-one".