18113945 has 4 divisors (see below), whose sum is σ = 21736740. Its totient is φ = 14491152.

The previous prime is 18113939. The next prime is 18113957. The reversal of 18113945 is 54931181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2778889 + 15335056 = 1667^2 + 3916^2 .

It is a cyclic number.

It is not a de Polignac number, because 18113945 - 2⁴ = 18113929 is a prime.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1811390 + ... + 1811399.

It is an arithmetic number, because the mean of its divisors is an integer number (5434185).

Almost surely, 2^18113945 is an apocalyptic number.

It is an amenable number.

18113945 is a deficient number, since it is larger than the sum of its proper divisors (3622795).

18113945 is an equidigital number, since it uses as much as digits as its factorization.

18113945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3622794.

The product of its digits is 4320, while the sum is 32.

The square root of 18113945 is about 4256.0480495408. The cubic root of 18113945 is about 262.6259773250.

The spelling of 18113945 in words is "eighteen million, one hundred thirteen thousand, nine hundred forty-five".