18223740 has 72 divisors (see below), whose sum is σ = 55757520. Its totient is φ = 4817664.

The previous prime is 18223703. The next prime is 18223757. The reversal of 18223740 is 4732281.

It is a congruent number.

It is an unprimeable number.

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, 24291 + ... + 25029.

It is an arithmetic number, because the mean of its divisors is an integer number (774410).

Almost surely, 2^18223740 is an apocalyptic number.

18223740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18223740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27878760).

18223740 is an abundant number, since it is smaller than the sum of its proper divisors (37533780).

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

18223740 is a wasteful number, since it uses less digits than its factorization.

18223740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 891 (or 886 counting only the distinct ones).

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

The square root of 18223740 is about 4268.9272657191. The cubic root of 18223740 is about 263.1555316700.

The spelling of 18223740 in words is "eighteen million, two hundred twenty-three thousand, seven hundred forty".