81123 has 8 divisors (see below), whose sum is σ = 123648. Its totient is φ = 46344.

The previous prime is 81119. The next prime is 81131. The reversal of 81123 is 32118.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81123 - 2² = 81119 is a prime.

It is a super-2 number, since 2×81123² = 13161882258, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81163) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1911 + ... + 1952.

It is an arithmetic number, because the mean of its divisors is an integer number (15456).

2⁸¹¹²³ is an apocalyptic number.

81123 is a deficient number, since it is larger than the sum of its proper divisors (42525).

81123 is a wasteful number, since it uses less digits than its factorization.

81123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3873.

The product of its digits is 48, while the sum is 15.

The square root of 81123 is about 284.8209964170. The cubic root of 81123 is about 43.2893768598.

It can be divided in two parts, 8112 and 3, that multiplied together give a square (24336 = 156²).

The spelling of 81123 in words is "eighty-one thousand, one hundred twenty-three".