18220605 has 64 divisors (see below), whose sum is σ = 33530112. Its totient is φ = 8386560.

The previous prime is 18220571. The next prime is 18220607. The reversal of 18220605 is 50602281.

It is not a de Polignac number, because 18220605 - 2⁹ = 18220093 is a prime.

It is a super-4 number, since 4×18220605⁴ (a number of 30 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18220607) 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 63 ways as a sum of consecutive naturals, for example, 343759 + ... + 343811.

It is an arithmetic number, because the mean of its divisors is an integer number (523908).

Almost surely, 2^18220605 is an apocalyptic number.

18220605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18220605 is a deficient number, since it is larger than the sum of its proper divisors (15309507).

18220605 is a wasteful number, since it uses less digits than its factorization.

18220605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158.

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 18220605 is about 4268.5600616601. The cubic root of 18220605 is about 263.1404407336.

Adding to 18220605 its reverse (50602281), we get a palindrome (68822886).

The spelling of 18220605 in words is "eighteen million, two hundred twenty thousand, six hundred five".