90998 has 8 divisors (see below), whose sum is σ = 137808. Its totient is φ = 45064.

The previous prime is 90997. The next prime is 91009. The reversal of 90998 is 89909.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 215 + ... + 477.

It is an arithmetic number, because the mean of its divisors is an integer number (17226).

2⁹⁰⁹⁹⁸ is an apocalyptic number.

90998 is a deficient number, since it is larger than the sum of its proper divisors (46810).

90998 is a wasteful number, since it uses less digits than its factorization.

90998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438.

The product of its (nonzero) digits is 5832, while the sum is 35.

The square root of 90998 is about 301.6587475940. The cubic root of 90998 is about 44.9790849308.

Subtracting from 90998 its reverse (89909), we obtain a square (1089 = 33²).

The spelling of 90998 in words is "ninety thousand, nine hundred ninety-eight".