81423 has 12 divisors (see below), whose sum is σ = 120120. Its totient is φ = 53136.

The previous prime is 81421. The next prime is 81439. The reversal of 81423 is 32418.

It is a happy number.

It is not a de Polignac number, because 81423 - 2¹ = 81421 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81396 and 81405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81421) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 693 + ... + 801.

It is an arithmetic number, because the mean of its divisors is an integer number (10010).

2⁸¹⁴²³ is an apocalyptic number.

81423 is a gapful number since it is divisible by the number (83) formed by its first and last digit.

81423 is a deficient number, since it is larger than the sum of its proper divisors (38697).

81423 is a wasteful number, since it uses less digits than its factorization.

81423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198 (or 195 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 81423 is about 285.3471569860. The cubic root of 81423 is about 43.3426738576.

It can be divided in two parts, 8 and 1423, that added together give a triangular number (1431 = T₅₃).

The spelling of 81423 in words is "eighty-one thousand, four hundred twenty-three".