90243989 has 8 divisors (see below), whose sum is σ = 98565120. Its totient is φ = 81942400.

The previous prime is 90243931. The next prime is 90244003. The reversal of 90243989 is 98934209.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90243989 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 (90243919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5804 + ... + 14634.

It is an arithmetic number, because the mean of its divisors is an integer number (12320640).

Almost surely, 2^90243989 is an apocalyptic number.

It is an amenable number.

90243989 is a deficient number, since it is larger than the sum of its proper divisors (8321131).

90243989 is a wasteful number, since it uses less digits than its factorization.

90243989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9771.

The product of its (nonzero) digits is 139968, while the sum is 44.

The square root of 90243989 is about 9499.6836263109. The cubic root of 90243989 is about 448.5450772005.

The spelling of 90243989 in words is "ninety million, two hundred forty-three thousand, nine hundred eighty-nine".