18238081 has 8 divisors (see below), whose sum is σ = 19258400. Its totient is φ = 17271684.

The previous prime is 18238079. The next prime is 18238097. The reversal of 18238081 is 18083281.

It is not a de Polignac number, because 18238081 - 2¹ = 18238079 is a prime.

It is a super-2 number, since 2×18238081² = 665255197125122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18238001) 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, 5530 + ... + 8188.

It is an arithmetic number, because the mean of its divisors is an integer number (2407300).

Almost surely, 2^18238081 is an apocalyptic number.

It is an amenable number.

18238081 is a deficient number, since it is larger than the sum of its proper divisors (1020319).

18238081 is an frugal number, since it uses more digits than its factorization.

18238081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2716 (or 2678 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 31.

The square root of 18238081 is about 4270.6066313815. The cubic root of 18238081 is about 263.2245428237.

The spelling of 18238081 in words is "eighteen million, two hundred thirty-eight thousand, eighty-one".