81356 has 18 divisors (see below), whose sum is σ = 159012. Its totient is φ = 36120.

The previous prime is 81353. The next prime is 81359. The reversal of 81356 is 65318.

81356 is nontrivially palindromic in base 14.

It is an interprime number because it is at equal distance from previous prime (81353) and next prime (81359).

It is not an unprimeable number, because it can be changed into a prime (81353) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1871 + ... + 1913.

It is an arithmetic number, because the mean of its divisors is an integer number (8834).

2⁸¹³⁵⁶ is an apocalyptic number.

81356 is a gapful number since it is divisible by the number (86) formed by its first and last digit.

It is an amenable number.

81356 is a deficient number, since it is larger than the sum of its proper divisors (77656).

81356 is a wasteful number, since it uses less digits than its factorization.

81356 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101 (or 56 counting only the distinct ones).

The product of its digits is 720, while the sum is 23.

The square root of 81356 is about 285.2297319706. The cubic root of 81356 is about 43.3307822298.

The spelling of 81356 in words is "eighty-one thousand, three hundred fifty-six".