81394 has 4 divisors (see below), whose sum is σ = 122094. Its totient is φ = 40696.

The previous prime is 81373. The next prime is 81401. The reversal of 81394 is 49318.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49318 = 2 ⋅24659.

It can be written as a sum of positive squares in only one way, i.e., 81225 + 169 = 285^2 + 13^2 .

It is a plaindrome in base 9.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20347 + ... + 20350.

2⁸¹³⁹⁴ is an apocalyptic number.

81394 is a deficient number, since it is larger than the sum of its proper divisors (40700).

81394 is a wasteful number, since it uses less digits than its factorization.

81394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40699.

The product of its digits is 864, while the sum is 25.

The square root of 81394 is about 285.2963371654. The cubic root of 81394 is about 43.3375275362.

The spelling of 81394 in words is "eighty-one thousand, three hundred ninety-four".