18156953 has 4 divisors (see below), whose sum is σ = 18317748. Its totient is φ = 17996160.

The previous prime is 18156949. The next prime is 18156961. The reversal of 18156953 is 35965181.

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 5139289 + 13017664 = 2267^2 + 3608^2 .

It is a cyclic number.

It is not a de Polignac number, because 18156953 - 2² = 18156949 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18156923) 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 3 ways as a sum of consecutive naturals, for example, 80228 + ... + 80453.

It is an arithmetic number, because the mean of its divisors is an integer number (4579437).

Almost surely, 2^18156953 is an apocalyptic number.

It is an amenable number.

18156953 is a deficient number, since it is larger than the sum of its proper divisors (160795).

18156953 is a wasteful number, since it uses less digits than its factorization.

18156953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160794.

The product of its digits is 32400, while the sum is 38.

The square root of 18156953 is about 4261.0976285460. The cubic root of 18156953 is about 262.8336642855.

The spelling of 18156953 in words is "eighteen million, one hundred fifty-six thousand, nine hundred fifty-three".