18211044 has 24 divisors (see below), whose sum is σ = 44729440. Its totient is φ = 5750784.

The previous prime is 18211033. The next prime is 18211049. The reversal of 18211044 is 44011281.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 18211044.

It is not an unprimeable number, because it can be changed into a prime (18211049) 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 7 ways as a sum of consecutive naturals, for example, 39709 + ... + 40164.

Almost surely, 2^18211044 is an apocalyptic number.

It is an amenable number.

18211044 is an abundant number, since it is smaller than the sum of its proper divisors (26518396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18211044 is a wasteful number, since it uses less digits than its factorization.

18211044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79899 (or 79897 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

The square root of 18211044 is about 4267.4399820033. The cubic root of 18211044 is about 263.0944062955.

The spelling of 18211044 in words is "eighteen million, two hundred eleven thousand, forty-four".