18402212 has 6 divisors (see below), whose sum is σ = 32203878. Its totient is φ = 9201104.

The previous prime is 18402199. The next prime is 18402217. The reversal of 18402212 is 21220481.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 12222016 + 6180196 = 3496^2 + 2486^2 .

It is not an unprimeable number, because it can be changed into a prime (18402217) 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 as a sum of consecutive naturals, namely, 2300273 + ... + 2300280.

It is an arithmetic number, because the mean of its divisors is an integer number (5367313).

Almost surely, 2^18402212 is an apocalyptic number.

It is an amenable number.

18402212 is a deficient number, since it is larger than the sum of its proper divisors (13801666).

18402212 is a wasteful number, since it uses less digits than its factorization.

18402212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4600557 (or 4600555 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 18402212 is about 4289.7799477362. The cubic root of 18402212 is about 264.0118031148.

Adding to 18402212 its reverse (21220481), we get a palindrome (39622693).

The spelling of 18402212 in words is "eighteen million, four hundred two thousand, two hundred twelve".