989390091 has 16 divisors (see below), whose sum is σ = 1348300800. Its totient is φ = 645058368.

The previous prime is 989390081. The next prime is 989390093. The reversal of 989390091 is 190093989.

It is not a de Polignac number, because 989390091 - 2²⁷ = 855172363 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 989390091.

It is not an unprimeable number, because it can be changed into a prime (989390093) 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 15 ways as a sum of consecutive naturals, for example, 292870 + ... + 296228.

It is an arithmetic number, because the mean of its divisors is an integer number (84268800).

Almost surely, 2^989390091 is an apocalyptic number.

989390091 is a deficient number, since it is larger than the sum of its proper divisors (358910709).

989390091 is a wasteful number, since it uses less digits than its factorization.

989390091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5498.

The product of its (nonzero) digits is 157464, while the sum is 48.

The square root of 989390091 is about 31454.5718616547. The cubic root of 989390091 is about 996.4507816187.

The spelling of 989390091 in words is "nine hundred eighty-nine million, three hundred ninety thousand, ninety-one".