18012813 has 16 divisors (see below), whose sum is σ = 29559936. Its totient is φ = 9501120.

The previous prime is 18012793. The next prime is 18012847. The reversal of 18012813 is 31821081.

It is not a de Polignac number, because 18012813 - 2²⁰ = 16964237 is a prime.

It is a super-3 number, since 3×18012813³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18012853) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32718 + ... + 33263.

It is an arithmetic number, because the mean of its divisors is an integer number (1847496).

Almost surely, 2^18012813 is an apocalyptic number.

18012813 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

18012813 is a deficient number, since it is larger than the sum of its proper divisors (11547123).

18012813 is a wasteful number, since it uses less digits than its factorization.

18012813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66004.

The product of its (nonzero) digits is 384, while the sum is 24.

The square root of 18012813 is about 4244.1504450243. The cubic root of 18012813 is about 262.1363090412.

Adding to 18012813 its reverse (31821081), we get a palindrome (49833894).

The spelling of 18012813 in words is "eighteen million, twelve thousand, eight hundred thirteen".