81560 has 16 divisors (see below), whose sum is σ = 183600. Its totient is φ = 32608.

The previous prime is 81559. The next prime is 81563. The reversal of 81560 is 6518.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 81560.

It is not an unprimeable number, because it can be changed into a prime (81563) 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, 980 + ... + 1059.

It is an arithmetic number, because the mean of its divisors is an integer number (11475).

2⁸¹⁵⁶⁰ is an apocalyptic number.

It is an amenable number.

81560 is an abundant number, since it is smaller than the sum of its proper divisors (102040).

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 (91800).

81560 is a wasteful number, since it uses less digits than its factorization.

81560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2050 (or 2046 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 81560 is about 285.5871145553. The cubic root of 81560 is about 43.3669692823.

The spelling of 81560 in words is "eighty-one thousand, five hundred sixty".