18222251 has 4 divisors (see below), whose sum is σ = 18298104. Its totient is φ = 18146400.

The previous prime is 18222223. The next prime is 18222257. The reversal of 18222251 is 15222281.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18222251 - 2¹⁴ = 18205867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18222257) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37565 + ... + 38046.

It is an arithmetic number, because the mean of its divisors is an integer number (4574526).

Almost surely, 2^18222251 is an apocalyptic number.

18222251 is a deficient number, since it is larger than the sum of its proper divisors (75853).

18222251 is an equidigital number, since it uses as much as digits as its factorization.

18222251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75852.

The product of its digits is 640, while the sum is 23.

The square root of 18222251 is about 4268.7528623709. The cubic root of 18222251 is about 263.1483642927.

The spelling of 18222251 in words is "eighteen million, two hundred twenty-two thousand, two hundred fifty-one".