18045972 has 72 divisors (see below), whose sum is σ = 54891200. Its totient is φ = 4883328.

The previous prime is 18045971. The next prime is 18045983. The reversal of 18045972 is 27954081.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18045971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2904 + ... + 6672.

Almost surely, 2^18045972 is an apocalyptic number.

18045972 is a gapful number since it is divisible by the number (12) 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 18045972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27445600).

18045972 is an abundant number, since it is smaller than the sum of its proper divisors (36845228).

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

18045972 is a wasteful number, since it uses less digits than its factorization.

18045972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3805 (or 3800 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 18045972 is about 4248.0550843886. The cubic root of 18045972 is about 262.2970621976.

It can be divided in two parts, 1804 and 5972, that added together give a 5-th power (7776 = 6⁵).

The spelling of 18045972 in words is "eighteen million, forty-five thousand, nine hundred seventy-two".