18327213 has 6 divisors (see below), whose sum is σ = 26472654. Its totient is φ = 12218136.

The previous prime is 18327209. The next prime is 18327223. The reversal of 18327213 is 31272381.

It can be written as a sum of positive squares in only one way, i.e., 17867529 + 459684 = 4227^2 + 678^2 .

It is not a de Polignac number, because 18327213 - 2² = 18327209 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18327203) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1018170 + ... + 1018187.

It is an arithmetic number, because the mean of its divisors is an integer number (4412109).

Almost surely, 2^18327213 is an apocalyptic number.

It is an amenable number.

18327213 is a deficient number, since it is larger than the sum of its proper divisors (8145441).

18327213 is a wasteful number, since it uses less digits than its factorization.

18327213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2036363 (or 2036360 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 18327213 is about 4281.0294322744. The cubic root of 18327213 is about 263.6526509701.

Adding to 18327213 its reverse (31272381), we get a palindrome (49599594).

It can be divided in two parts, 1832 and 7213, that added together give a triangular number (9045 = T₁₃₄).

The spelling of 18327213 in words is "eighteen million, three hundred twenty-seven thousand, two hundred thirteen".