90865 has 8 divisors (see below), whose sum is σ = 115560. Its totient is φ = 68352.

The previous prime is 90863. The next prime is 90887. The reversal of 90865 is 56809.

It can be written as a sum of positive squares in 4 ways, for example, as 17424 + 73441 = 132^2 + 271^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 90865 - 2¹ = 90863 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 450 + ... + 619.

It is an arithmetic number, because the mean of its divisors is an integer number (14445).

2⁹⁰⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

90865 is a deficient number, since it is larger than the sum of its proper divisors (24695).

90865 is a wasteful number, since it uses less digits than its factorization.

90865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1091.

The product of its (nonzero) digits is 2160, while the sum is 28.

The square root of 90865 is about 301.4382192092. The cubic root of 90865 is about 44.9571608770.

Adding to 90865 its product of nonzero digits (2160), we get a square (93025 = 305²).

The spelling of 90865 in words is "ninety thousand, eight hundred sixty-five".