18225972 has 72 divisors (see below), whose sum is σ = 50633856. Its totient is φ = 5712768.

The previous prime is 18225967. The next prime is 18225979. The reversal of 18225972 is 27952281.

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 (18225979) 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, 15973 + ... + 17075.

It is an arithmetic number, because the mean of its divisors is an integer number (703248).

Almost surely, 2^18225972 is an apocalyptic number.

18225972 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 18225972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25316928).

18225972 is an abundant number, since it is smaller than the sum of its proper divisors (32407884).

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

18225972 is a wasteful number, since it uses less digits than its factorization.

18225972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1139 (or 1125 counting only the distinct ones).

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

The square root of 18225972 is about 4269.1886817052. The cubic root of 18225972 is about 263.1662747844.

The spelling of 18225972 in words is "eighteen million, two hundred twenty-five thousand, nine hundred seventy-two".