18058509 has 18 divisors (see below), whose sum is σ = 30343950. Its totient is φ = 10318896.

The previous prime is 18058507. The next prime is 18058541. The reversal of 18058509 is 90585081.

It can be written as a sum of positive squares in only one way, i.e., 15093225 + 2965284 = 3885^2 + 1722^2 .

It is not a de Polignac number, because 18058509 - 2¹ = 18058507 is a prime.

It is a super-2 number, since 2×18058509² = 652219494606162, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18058507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 20034 + ... + 20915.

It is an arithmetic number, because the mean of its divisors is an integer number (1685775).

Almost surely, 2^18058509 is an apocalyptic number.

It is an amenable number.

18058509 is a deficient number, since it is larger than the sum of its proper divisors (12285441).

18058509 is a wasteful number, since it uses less digits than its factorization.

18058509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40969 (or 40959 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 36.

The square root of 18058509 is about 4249.5304446491. The cubic root of 18058509 is about 262.3577896376.

The spelling of 18058509 in words is "eighteen million, fifty-eight thousand, five hundred nine".