83815 has 4 divisors (see below), whose sum is σ = 100584. Its totient is φ = 67048.

The previous prime is 83813. The next prime is 83833. The reversal of 83815 is 51838.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51838 = 2 ⋅25919.

It is a cyclic number.

It is not a de Polignac number, because 83815 - 2¹ = 83813 is a prime.

It is a Duffinian number.

83815 is a lucky number.

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 83815.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (83813) 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, 8377 + ... + 8386.

It is an arithmetic number, because the mean of its divisors is an integer number (25146).

2⁸³⁸¹⁵ is an apocalyptic number.

83815 is a deficient number, since it is larger than the sum of its proper divisors (16769).

83815 is a wasteful number, since it uses less digits than its factorization.

83815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16768.

The product of its digits is 960, while the sum is 25.

The square root of 83815 is about 289.5082036834. The cubic root of 83815 is about 43.7630165351.

It can be divided in two parts, 8381 and 5, that multiplied together give a triangular number (41905 = T₂₈₉).

The spelling of 83815 in words is "eighty-three thousand, eight hundred fifteen".