81418144 has 24 divisors (see below), whose sum is σ = 161189028. Its totient is φ = 40481280.

The previous prime is 81418133. The next prime is 81418153. The reversal of 81418144 is 44181418.

It can be written as a sum of positive squares in 2 ways, for example, as 52128400 + 29289744 = 7220^2 + 5412^2 .

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1237 + ... + 12820.

Almost surely, 2^81418144 is an apocalyptic number.

It is an amenable number.

81418144 is a deficient number, since it is larger than the sum of its proper divisors (79770884).

81418144 is a wasteful number, since it uses less digits than its factorization.

81418144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14248 (or 14240 counting only the distinct ones).

The product of its digits is 4096, while the sum is 31.

The square root of 81418144 is about 9023.2003191772. The cubic root of 81418144 is about 433.4181220017.

The spelling of 81418144 in words is "eighty-one million, four hundred eighteen thousand, one hundred forty-four".