81009418 has 8 divisors (see below), whose sum is σ = 138873312. Its totient is φ = 34718316.

The previous prime is 81009413. The next prime is 81009421. The reversal of 81009418 is 81490018.

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

It is a self number, because there is not a number n which added to its sum of digits gives 81009418.

It is not an unprimeable number, because it can be changed into a prime (81009413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2893180 + ... + 2893207.

It is an arithmetic number, because the mean of its divisors is an integer number (17359164).

Almost surely, 2^81009418 is an apocalyptic number.

81009418 is a deficient number, since it is larger than the sum of its proper divisors (57863894).

81009418 is a wasteful number, since it uses less digits than its factorization.

81009418 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5786396.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 81009418 is about 9000.5232070141. The cubic root of 81009418 is about 432.6916397096.

The spelling of 81009418 in words is "eighty-one million, nine thousand, four hundred eighteen".