18491072 has 42 divisors (see below), whose sum is σ = 37775388. Its totient is φ = 8979328.

The previous prime is 18491071. The next prime is 18491089. The reversal of 18491072 is 27019481.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is not an unprimeable number, because it can be changed into a prime (18491071) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 222743 + ... + 222825.

It is an arithmetic number, because the mean of its divisors is an integer number (899414).

Almost surely, 2^18491072 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 18491072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18887694).

18491072 is an abundant number, since it is smaller than the sum of its proper divisors (19284316).

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

18491072 is an frugal number, since it uses more digits than its factorization.

18491072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 18491072 is about 4300.1246493561. The cubic root of 18491072 is about 264.4360714708.

The spelling of 18491072 in words is "eighteen million, four hundred ninety-one thousand, seventy-two".