18043722 has 48 divisors (see below), whose sum is σ = 40989312. Its totient is φ = 5948640.

The previous prime is 18043721. The next prime is 18043733. The reversal of 18043722 is 22734081.

It is a super-2 number, since 2×18043722² = 651151807226568, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (18043721) 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 23 ways as a sum of consecutive naturals, for example, 66447 + ... + 66717.

It is an arithmetic number, because the mean of its divisors is an integer number (853944).

Almost surely, 2^18043722 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18043722, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20494656).

18043722 is an abundant number, since it is smaller than the sum of its proper divisors (22945590).

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

18043722 is a wasteful number, since it uses less digits than its factorization.

18043722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 425 (or 413 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 18043722 is about 4247.7902490589. The cubic root of 18043722 is about 262.2861605419.

The spelling of 18043722 in words is "eighteen million, forty-three thousand, seven hundred twenty-two".