18220267 has 4 divisors (see below), whose sum is σ = 19621840. Its totient is φ = 16818696.

The previous prime is 18220247. The next prime is 18220271. The reversal of 18220267 is 76202281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76202281 = 2339 ⋅32579.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18220267 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18220247) 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, 700767 + ... + 700792.

It is an arithmetic number, because the mean of its divisors is an integer number (4905460).

Almost surely, 2^18220267 is an apocalyptic number.

18220267 is a deficient number, since it is larger than the sum of its proper divisors (1401573).

18220267 is a wasteful number, since it uses less digits than its factorization.

18220267 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1401572.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 18220267 is about 4268.5204696710. The cubic root of 18220267 is about 263.1388136011.

It can be divided in two parts, 182 and 20267, that added together give a square (20449 = 143²).

The spelling of 18220267 in words is "eighteen million, two hundred twenty thousand, two hundred sixty-seven".