18287244 has 18 divisors (see below), whose sum is σ = 46226180. Its totient is φ = 6095736.

The previous prime is 18287221. The next prime is 18287249. The reversal of 18287244 is 44278281.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 507979 = 18287244 / (1 + 8 + 2 + 8 + 7 + 2 + 4 + 4).

It is a junction number, because it is equal to n+sod(n) for n = 18287199 and 18287208.

It is not an unprimeable number, because it can be changed into a prime (18287249) 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, 253954 + ... + 254025.

Almost surely, 2^18287244 is an apocalyptic number.

It is an amenable number.

18287244 is an abundant number, since it is smaller than the sum of its proper divisors (27938936).

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

18287244 is a wasteful number, since it uses less digits than its factorization.

18287244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507989 (or 507984 counting only the distinct ones).

The product of its digits is 28672, while the sum is 36.

The square root of 18287244 is about 4276.3587314443. The cubic root of 18287244 is about 263.4608487092.

The spelling of 18287244 in words is "eighteen million, two hundred eighty-seven thousand, two hundred forty-four".