81893 has 4 divisors (see below), whose sum is σ = 93600. Its totient is φ = 70188.

The previous prime is 81883. The next prime is 81899. The reversal of 81893 is 39818.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81893 - 2⁸ = 81637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81899) 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, 5843 + ... + 5856.

It is an arithmetic number, because the mean of its divisors is an integer number (23400).

2⁸¹⁸⁹³ is an apocalyptic number.

It is an amenable number.

81893 is a deficient number, since it is larger than the sum of its proper divisors (11707).

81893 is a wasteful number, since it uses less digits than its factorization.

81893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11706.

The product of its digits is 1728, while the sum is 29.

The square root of 81893 is about 286.1695301740. The cubic root of 81893 is about 43.4259099040.

It can be divided in two parts, 8189 and 3, that added together give a 13-th power (8192 = 2¹³).

The spelling of 81893 in words is "eighty-one thousand, eight hundred ninety-three".