18121369 has 4 divisors (see below), whose sum is σ = 20710144. Its totient is φ = 15532596.

The previous prime is 18121351. The next prime is 18121387. The reversal of 18121369 is 96312181.

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.

It is an interprime number because it is at equal distance from previous prime (18121351) and next prime (18121387).

It is a cyclic number.

It is not a de Polignac number, because 18121369 - 2⁷ = 18121241 is a prime.

It is a super-2 number, since 2×18121369² = 656768028868322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18121369.

It is not an unprimeable number, because it can be changed into a prime (18121399) 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, 1294377 + ... + 1294390.

It is an arithmetic number, because the mean of its divisors is an integer number (5177536).

Almost surely, 2^18121369 is an apocalyptic number.

It is an amenable number.

18121369 is a deficient number, since it is larger than the sum of its proper divisors (2588775).

18121369 is an equidigital number, since it uses as much as digits as its factorization.

18121369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2588774.

The product of its digits is 2592, while the sum is 31.

The square root of 18121369 is about 4256.9201307988. The cubic root of 18121369 is about 262.6618515083.

The spelling of 18121369 in words is "eighteen million, one hundred twenty-one thousand, three hundred sixty-nine".