90859 has 4 divisors (see below), whose sum is σ = 93016. Its totient is φ = 88704.

The previous prime is 90847. The next prime is 90863. The reversal of 90859 is 95809.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 95809 = 7 ⋅13687.

It is a cyclic number.

It is not a de Polignac number, because 90859 - 2⁷ = 90731 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90859.

It is not an unprimeable number, because it can be changed into a prime (90059) 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, 1014 + ... + 1099.

It is an arithmetic number, because the mean of its divisors is an integer number (23254).

2⁹⁰⁸⁵⁹ is an apocalyptic number.

90859 is a deficient number, since it is larger than the sum of its proper divisors (2157).

90859 is a wasteful number, since it uses less digits than its factorization.

90859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2156.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 90859 is about 301.4282667568. The cubic root of 90859 is about 44.9561713178.

Subtracting 90859 from its reverse (95809), we obtain a triangular number (4950 = T₉₉).

It can be divided in two parts, 90 and 859, that added together give a palindrome (949).

The spelling of 90859 in words is "ninety thousand, eight hundred fifty-nine".