18091305 has 12 divisors (see below), whose sum is σ = 31358340. Its totient is φ = 9648672.

The previous prime is 18091301. The next prime is 18091309. The reversal of 18091305 is 50319081.

It is an interprime number because it is at equal distance from previous prime (18091301) and next prime (18091309).

It can be written as a sum of positive squares in 2 ways, for example, as 9865881 + 8225424 = 3141^2 + 2868^2 .

It is not a de Polignac number, because 18091305 - 2² = 18091301 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18091301) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 200970 + ... + 201059.

It is an arithmetic number, because the mean of its divisors is an integer number (2613195).

Almost surely, 2^18091305 is an apocalyptic number.

18091305 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18091305 is a deficient number, since it is larger than the sum of its proper divisors (13267035).

18091305 is a wasteful number, since it uses less digits than its factorization.

18091305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 402040 (or 402037 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 18091305 is about 4253.3874735321. The cubic root of 18091305 is about 262.5165159676.

The spelling of 18091305 in words is "eighteen million, ninety-one thousand, three hundred five".