18238213 has 8 divisors (see below), whose sum is σ = 21003840. Its totient is φ = 15512640.

The previous prime is 18238193. The next prime is 18238217. The reversal of 18238213 is 31283281.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18238213 - 2²¹ = 16141061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18238217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9028 + ... + 10861.

It is an arithmetic number, because the mean of its divisors is an integer number (2625480).

Almost surely, 2^18238213 is an apocalyptic number.

It is an amenable number.

18238213 is a deficient number, since it is larger than the sum of its proper divisors (2765627).

18238213 is a wasteful number, since it uses less digits than its factorization.

18238213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20027.

The product of its digits is 2304, while the sum is 28.

The square root of 18238213 is about 4270.6220858325. The cubic root of 18238213 is about 263.2251778604.

The spelling of 18238213 in words is "eighteen million, two hundred thirty-eight thousand, two hundred thirteen".