81359806 has 16 divisors (see below), whose sum is σ = 133436160. Its totient is φ = 36897880.

The previous prime is 81359797. The next prime is 81359813. The reversal of 81359806 is 60895318.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 6315 + ... + 14233.

It is an arithmetic number, because the mean of its divisors is an integer number (8339760).

Almost surely, 2^81359806 is an apocalyptic number.

81359806 is a deficient number, since it is larger than the sum of its proper divisors (52076354).

81359806 is a wasteful number, since it uses less digits than its factorization.

81359806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8399.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 81359806 is about 9019.9670731106. The cubic root of 81359806 is about 433.3145792015.

The spelling of 81359806 in words is "eighty-one million, three hundred fifty-nine thousand, eight hundred six".