18357109 has 2 divisors, whose sum is σ = 18357110. Its totient is φ = 18357108.

The previous prime is 18357107. The next prime is 18357113. The reversal of 18357109 is 90175381.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17098225 + 1258884 = 4135^2 + 1122^2 .

It is a cyclic number.

It is not a de Polignac number, because 18357109 - 2¹ = 18357107 is a prime.

Together with 18357107, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18357103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9178554 + 9178555.

It is an arithmetic number, because the mean of its divisors is an integer number (9178555).

Almost surely, 2^18357109 is an apocalyptic number.

It is an amenable number.

18357109 is a deficient number, since it is larger than the sum of its proper divisors (1).

18357109 is an equidigital number, since it uses as much as digits as its factorization.

18357109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7560, while the sum is 34.

The square root of 18357109 is about 4284.5196930344. The cubic root of 18357109 is about 263.7959329419.

The spelling of 18357109 in words is "eighteen million, three hundred fifty-seven thousand, one hundred nine".