18409113 has 40 divisors (see below), whose sum is σ = 30187080. Its totient is φ = 11128320.

The previous prime is 18409109. The next prime is 18409163. The reversal of 18409113 is 31190481.

It can be written as a sum of positive squares in 4 ways, for example, as 3640464 + 14768649 = 1908^2 + 3843^2 .

It is not a de Polignac number, because 18409113 - 2² = 18409109 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (18409163) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 39703 + ... + 40163.

It is an arithmetic number, because the mean of its divisors is an integer number (754677).

Almost surely, 2^18409113 is an apocalyptic number.

It is an amenable number.

18409113 is a deficient number, since it is larger than the sum of its proper divisors (11777967).

18409113 is a wasteful number, since it uses less digits than its factorization.

18409113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519 (or 510 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 18409113 is about 4290.5842259534. The cubic root of 18409113 is about 264.0448012810.

Adding to 18409113 its reverse (31190481), we get a palindrome (49599594).

The spelling of 18409113 in words is "eighteen million, four hundred nine thousand, one hundred thirteen".