18861223 has 4 divisors (see below), whose sum is σ = 19511640. Its totient is φ = 18210808.

The previous prime is 18861209. The next prime is 18861233. The reversal of 18861223 is 32216881.

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 18861223 - 2⁵ = 18861191 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18861233) 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, 325165 + ... + 325222.

It is an arithmetic number, because the mean of its divisors is an integer number (4877910).

Almost surely, 2^18861223 is an apocalyptic number.

18861223 is a deficient number, since it is larger than the sum of its proper divisors (650417).

18861223 is an equidigital number, since it uses as much as digits as its factorization.

18861223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 650416.

The product of its digits is 4608, while the sum is 31.

The square root of 18861223 is about 4342.9509552837. The cubic root of 18861223 is about 266.1889051412.

The spelling of 18861223 in words is "eighteen million, eight hundred sixty-one thousand, two hundred twenty-three".