18133812 has 18 divisors (see below), whose sum is σ = 45838338. Its totient is φ = 6044592.

The previous prime is 18133793. The next prime is 18133813. The reversal of 18133812 is 21833181.

It can be written as a sum of positive squares in only one way, i.e., 14470416 + 3663396 = 3804^2 + 1914^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18133813) 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 5 ways as a sum of consecutive naturals, for example, 251823 + ... + 251894.

Almost surely, 2^18133812 is an apocalyptic number.

18133812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18133812 is an abundant number, since it is smaller than the sum of its proper divisors (27704526).

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

18133812 is a wasteful number, since it uses less digits than its factorization.

18133812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503727 (or 503722 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 18133812 is about 4258.3813826382. The cubic root of 18133812 is about 262.7219564898.

Adding to 18133812 its reverse (21833181), we get a palindrome (39966993).

It can be divided in two parts, 1813 and 3812, that added together give a square (5625 = 75²).

The spelling of 18133812 in words is "eighteen million, one hundred thirty-three thousand, eight hundred twelve".