81330984442 has 8 divisors (see below), whose sum is σ = 122050250100. Its totient is φ = 40647567744.

The previous prime is 81330984407. The next prime is 81330984443. The reversal of 81330984442 is 24448903318.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 81100217961 + 230766481 = 284781^2 + 15191^2 .

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

It is a super-2 number, since 2×81330984442² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81330984392 and 81330984401.

It is not an unprimeable number, because it can be changed into a prime (81330984443) 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, 8956567 + ... + 8965642.

Almost surely, 2^81330984442 is an apocalyptic number.

81330984442 is a deficient number, since it is larger than the sum of its proper divisors (40719265658).

81330984442 is a wasteful number, since it uses less digits than its factorization.

81330984442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17924480.

The product of its (nonzero) digits is 663552, while the sum is 46.

The spelling of 81330984442 in words is "eighty-one billion, three hundred thirty million, nine hundred eighty-four thousand, four hundred forty-two".