81143233 has 4 divisors (see below), whose sum is σ = 81507328. Its totient is φ = 80779140.

The previous prime is 81143219. The next prime is 81143267. The reversal of 81143233 is 33234118.

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, and also an emirpimes, since its reverse is a distinct semiprime: 33234118 = 2 ⋅16617059.

It is a cyclic number.

It is not a de Polignac number, because 81143233 - 2⁵ = 81143201 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81143198 and 81143207.

It is not an unprimeable number, because it can be changed into a prime (81141233) 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, 181713 + ... + 182158.

It is an arithmetic number, because the mean of its divisors is an integer number (20376832).

Almost surely, 2^81143233 is an apocalyptic number.

It is an amenable number.

81143233 is a deficient number, since it is larger than the sum of its proper divisors (364095).

81143233 is a wasteful number, since it uses less digits than its factorization.

81143233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364094.

The product of its digits is 1728, while the sum is 25.

The square root of 81143233 is about 9007.9538742158. The cubic root of 81143233 is about 432.9297551512.

It can be divided in two parts, 811 and 43233, that added together give a palindrome (44044).

The spelling of 81143233 in words is "eighty-one million, one hundred forty-three thousand, two hundred thirty-three".