18201222 has 24 divisors (see below), whose sum is σ = 42470064. Its totient is φ = 5600304.

The previous prime is 18201217. The next prime is 18201223. The reversal of 18201222 is 22210281.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 18201195 and 18201204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18201223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38658 + ... + 39125.

It is an arithmetic number, because the mean of its divisors is an integer number (1769586).

Almost surely, 2^18201222 is an apocalyptic number.

18201222 is an abundant number, since it is smaller than the sum of its proper divisors (24268842).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18201222 is a wasteful number, since it uses less digits than its factorization.

18201222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77804 (or 77801 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 18201222 is about 4266.2890197454. The cubic root of 18201222 is about 263.0470984096.

The spelling of 18201222 in words is "eighteen million, two hundred one thousand, two hundred twenty-two".