81884235619 has 4 divisors (see below), whose sum is σ = 81963658800. Its totient is φ = 81804812440.

The previous prime is 81884235593. The next prime is 81884235677. The reversal of 81884235619 is 91653248818.

It is a happy number.

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 81884235619 - 2⁷ = 81884235491 is a prime.

It is a super-2 number, since 2×81884235619² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81884235619.

It is not an unprimeable number, because it can be changed into a prime (81884235919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39710044 + ... + 39712105.

It is an arithmetic number, because the mean of its divisors is an integer number (20490914700).

Almost surely, 2^81884235619 is an apocalyptic number.

81884235619 is a deficient number, since it is larger than the sum of its proper divisors (79423181).

81884235619 is a wasteful number, since it uses less digits than its factorization.

81884235619 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79423180.

The product of its digits is 3317760, while the sum is 55.

The spelling of 81884235619 in words is "eighty-one billion, eight hundred eighty-four million, two hundred thirty-five thousand, six hundred nineteen".