90491 has 4 divisors (see below), whose sum is σ = 95832. Its totient is φ = 85152.

The previous prime is 90481. The next prime is 90499. The reversal of 90491 is 19409.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19409 = 13 ⋅1493.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90491 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (90499) 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, 2645 + ... + 2678.

It is an arithmetic number, because the mean of its divisors is an integer number (23958).

2⁹⁰⁴⁹¹ is an apocalyptic number.

90491 is a deficient number, since it is larger than the sum of its proper divisors (5341).

90491 is a wasteful number, since it uses less digits than its factorization.

90491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5340.

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 90491 is about 300.8172202518. The cubic root of 90491 is about 44.8953948878.

The spelling of 90491 in words is "ninety thousand, four hundred ninety-one".