81882439 has 4 divisors (see below), whose sum is σ = 84523840. Its totient is φ = 79241040.

The previous prime is 81882433. The next prime is 81882481. The reversal of 81882439 is 93428818.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81882439 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81882395 and 81882404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81882433) 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, 1320654 + ... + 1320715.

It is an arithmetic number, because the mean of its divisors is an integer number (21130960).

Almost surely, 2^81882439 is an apocalyptic number.

81882439 is a deficient number, since it is larger than the sum of its proper divisors (2641401).

81882439 is a wasteful number, since it uses less digits than its factorization.

81882439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2641400.

The product of its digits is 110592, while the sum is 43.

The square root of 81882439 is about 9048.8915895816. The cubic root of 81882439 is about 434.2404307472.

The spelling of 81882439 in words is "eighty-one million, eight hundred eighty-two thousand, four hundred thirty-nine".