83665 has 8 divisors (see below), whose sum is σ = 104040. Its totient is φ = 64512.

The previous prime is 83663. The next prime is 83689. The reversal of 83665 is 56638.

83665 = T₆₁ + T₆₂ + ... + T₈₉.

It can be written as a sum of positive squares in 4 ways, for example, as 33489 + 50176 = 183^2 + 224^2 .

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

It is a 3-Lehmer number, since φ(83665) divides (83665-1)³.

It is a cyclic number.

It is not a de Polignac number, because 83665 - 2¹ = 83663 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (83663) 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, 144 + ... + 433.

It is an arithmetic number, because the mean of its divisors is an integer number (13005).

It is a Poulet number, since it divides 2⁸³⁶⁶⁴-1.

2⁸³⁶⁶⁵ is an apocalyptic number.

83665 is the 145-th decagonal number.

It is an amenable number.

83665 is a deficient number, since it is larger than the sum of its proper divisors (20375).

83665 is a wasteful number, since it uses less digits than its factorization.

83665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611.

The product of its digits is 4320, while the sum is 28.

The square root of 83665 is about 289.2490276561. The cubic root of 83665 is about 43.7368940335.

The spelling of 83665 in words is "eighty-three thousand, six hundred sixty-five".