18157224 has 64 divisors (see below), whose sum is σ = 48522240. Its totient is φ = 5642240.

The previous prime is 18157211. The next prime is 18157253. The reversal of 18157224 is 42275181.

It is a junction number, because it is equal to n+sod(n) for n = 18157191 and 18157200.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 77812 + ... + 78044.

It is an arithmetic number, because the mean of its divisors is an integer number (758160).

Almost surely, 2^18157224 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 18157224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24261120).

18157224 is an abundant number, since it is smaller than the sum of its proper divisors (30365016).

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

18157224 is a wasteful number, since it uses less digits than its factorization.

18157224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450 (or 446 counting only the distinct ones).

The product of its digits is 4480, while the sum is 30.

The square root of 18157224 is about 4261.1294277457. The cubic root of 18157224 is about 262.8349719125.

It can be divided in two parts, 18157 and 224, that added together give a palindrome (18381).

The spelling of 18157224 in words is "eighteen million, one hundred fifty-seven thousand, two hundred twenty-four".