81289589906 has 8 divisors (see below), whose sum is σ = 139353582720. Its totient is φ = 34838395668.

The previous prime is 81289589879. The next prime is 81289589917. The reversal of 81289589906 is 60998598218.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2903199626 + ... + 2903199653.

It is an arithmetic number, because the mean of its divisors is an integer number (17419197840).

Almost surely, 2^81289589906 is an apocalyptic number.

81289589906 is a deficient number, since it is larger than the sum of its proper divisors (58063992814).

81289589906 is a wasteful number, since it uses less digits than its factorization.

81289589906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5806399288.

The product of its (nonzero) digits is 22394880, while the sum is 65.

The spelling of 81289589906 in words is "eighty-one billion, two hundred eighty-nine million, five hundred eighty-nine thousand, nine hundred six".