18306613 has 4 divisors (see below), whose sum is σ = 19714828. Its totient is φ = 16898400.

The previous prime is 18306599. The next prime is 18306661. The reversal of 18306613 is 31660381.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31660381 = 67 ⋅472543.

It can be written as a sum of positive squares in 2 ways, for example, as 2490084 + 15816529 = 1578^2 + 3977^2 .

It is a cyclic number.

It is not a de Polignac number, because 18306613 - 2⁵ = 18306581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18306313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 704088 + ... + 704113.

It is an arithmetic number, because the mean of its divisors is an integer number (4928707).

Almost surely, 2^18306613 is an apocalyptic number.

18306613 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

18306613 is a deficient number, since it is larger than the sum of its proper divisors (1408215).

18306613 is a wasteful number, since it uses less digits than its factorization.

18306613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1408214.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 18306613 is about 4278.6227924415. The cubic root of 18306613 is about 263.5538310566.

Adding to 18306613 its reverse (31660381), we get a palindrome (49966994).

The spelling of 18306613 in words is "eighteen million, three hundred six thousand, six hundred thirteen".