18238385 has 32 divisors (see below), whose sum is σ = 25989120. Its totient is φ = 12139200.

The previous prime is 18238369. The next prime is 18238387. The reversal of 18238385 is 58383281.

It is not a de Polignac number, because 18238385 - 2⁴ = 18238369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18238387) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32114 + ... + 32676.

It is an arithmetic number, because the mean of its divisors is an integer number (812160).

Almost surely, 2^18238385 is an apocalyptic number.

It is an amenable number.

18238385 is a deficient number, since it is larger than the sum of its proper divisors (7750735).

18238385 is a wasteful number, since it uses less digits than its factorization.

18238385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 629.

The product of its digits is 46080, while the sum is 38.

The square root of 18238385 is about 4270.6422233664. The cubic root of 18238385 is about 263.2260053280.

Subtracting 18238385 from its reverse (58383281), we obtain a square (40144896 = 6336²).

The spelling of 18238385 in words is "eighteen million, two hundred thirty-eight thousand, three hundred eighty-five".