81522 has 24 divisors (see below), whose sum is σ = 202176. Its totient is φ = 23256.

The previous prime is 81517. The next prime is 81527. The reversal of 81522 is 22518.

It is an interprime number because it is at equal distance from previous prime (81517) and next prime (81527).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 81495 and 81504.

It is not an unprimeable number, because it can be changed into a prime (81527) by changing a digit.

81522 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 198 + ... + 449.

It is an arithmetic number, because the mean of its divisors is an integer number (8424).

2⁸¹⁵²² is an apocalyptic number.

81522 is an abundant number, since it is smaller than the sum of its proper divisors (120654).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101088).

81522 is a wasteful number, since it uses less digits than its factorization.

81522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662 (or 659 counting only the distinct ones).

The product of its digits is 160, while the sum is 18.

The square root of 81522 is about 285.5205771919. The cubic root of 81522 is about 43.3602331337.

The spelling of 81522 in words is "eighty-one thousand, five hundred twenty-two".