18109313 has 4 divisors (see below), whose sum is σ = 18217920. Its totient is φ = 18000708.

The previous prime is 18109307. The next prime is 18109339. The reversal of 18109313 is 31390181.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 31390181 = 421 ⋅74561.

It is a cyclic number.

It is not a de Polignac number, because 18109313 - 2⁴ = 18109297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18109373) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54053 + ... + 54386.

It is an arithmetic number, because the mean of its divisors is an integer number (4554480).

Almost surely, 2^18109313 is an apocalyptic number.

It is an amenable number.

18109313 is a deficient number, since it is larger than the sum of its proper divisors (108607).

18109313 is a wasteful number, since it uses less digits than its factorization.

18109313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108606.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 18109313 is about 4255.5038479597. The cubic root of 18109313 is about 262.6035896520.

Adding to 18109313 its reverse (31390181), we get a palindrome (49499494).

The spelling of 18109313 in words is "eighteen million, one hundred nine thousand, three hundred thirteen".