18406224 has 80 divisors (see below), whose sum is σ = 53389440. Its totient is φ = 6071040.

The previous prime is 18406183. The next prime is 18406229. The reversal of 18406224 is 42260481.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18406229) 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 15 ways as a sum of consecutive naturals, for example, 59029 + ... + 59339.

It is an arithmetic number, because the mean of its divisors is an integer number (667368).

Almost surely, 2^18406224 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18406224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26694720).

18406224 is an abundant number, since it is smaller than the sum of its proper divisors (34983216).

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

18406224 is a wasteful number, since it uses less digits than its factorization.

18406224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 465 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 18406224 is about 4290.2475453055. The cubic root of 18406224 is about 264.0309880980.

The spelling of 18406224 in words is "eighteen million, four hundred six thousand, two hundred twenty-four".