81436038443 has 4 divisors (see below), whose sum is σ = 83168720160. Its totient is φ = 79703356728.

The previous prime is 81436038427. The next prime is 81436038457. The reversal of 81436038443 is 34483063418.

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

It is a cyclic number.

It is not a de Polignac number, because 81436038443 - 2⁴ = 81436038427 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81436038394 and 81436038403.

It is not an unprimeable number, because it can be changed into a prime (81436038413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 866340788 + ... + 866340881.

It is an arithmetic number, because the mean of its divisors is an integer number (20792180040).

Almost surely, 2^81436038443 is an apocalyptic number.

81436038443 is a deficient number, since it is larger than the sum of its proper divisors (1732681717).

81436038443 is a wasteful number, since it uses less digits than its factorization.

81436038443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1732681716.

The product of its (nonzero) digits is 663552, while the sum is 44.

The spelling of 81436038443 in words is "eighty-one billion, four hundred thirty-six million, thirty-eight thousand, four hundred forty-three".