18298381 has 4 divisors (see below), whose sum is σ = 18307072. Its totient is φ = 18289692.

The previous prime is 18298361. The next prime is 18298393. The reversal of 18298381 is 18389281.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 18298381 - 2¹³ = 18290189 is a prime.

It is a super-2 number, since 2×18298381² = 669661494442322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18298361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1030 + ... + 6136.

It is an arithmetic number, because the mean of its divisors is an integer number (4576768).

Almost surely, 2^18298381 is an apocalyptic number.

It is an amenable number.

18298381 is a deficient number, since it is larger than the sum of its proper divisors (8691).

18298381 is an equidigital number, since it uses as much as digits as its factorization.

18298381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8690.

The product of its digits is 27648, while the sum is 40.

The square root of 18298381 is about 4277.6606924813. The cubic root of 18298381 is about 263.5143207365.

The spelling of 18298381 in words is "eighteen million, two hundred ninety-eight thousand, three hundred eighty-one".