18227905 has 4 divisors (see below), whose sum is σ = 21873492. Its totient is φ = 14582320.

The previous prime is 18227887. The next prime is 18227933. The reversal of 18227905 is 50972281.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2163841 + 16064064 = 1471^2 + 4008^2 .

It is not a de Polignac number, because 18227905 - 2¹³ = 18219713 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1822786 + ... + 1822795.

It is an arithmetic number, because the mean of its divisors is an integer number (5468373).

Almost surely, 2^18227905 is an apocalyptic number.

It is an amenable number.

18227905 is a deficient number, since it is larger than the sum of its proper divisors (3645587).

18227905 is an equidigital number, since it uses as much as digits as its factorization.

18227905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3645586.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 18227905 is about 4269.4150653222. The cubic root of 18227905 is about 263.1755780363.

The spelling of 18227905 in words is "eighteen million, two hundred twenty-seven thousand, nine hundred five".