18955913 has 4 divisors (see below), whose sum is σ = 19012500. Its totient is φ = 18899328.

The previous prime is 18955907. The next prime is 18955919. The reversal of 18955913 is 31955981.

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

It is an interprime number because it is at equal distance from previous prime (18955907) and next prime (18955919).

It can be written as a sum of positive squares in 2 ways, for example, as 12054784 + 6901129 = 3472^2 + 2627^2 .

It is a cyclic number.

It is not a de Polignac number, because 18955913 - 2¹⁰ = 18954889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18955919) 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, 27788 + ... + 28461.

It is an arithmetic number, because the mean of its divisors is an integer number (4753125).

Almost surely, 2^18955913 is an apocalyptic number.

It is an amenable number.

18955913 is a deficient number, since it is larger than the sum of its proper divisors (56587).

18955913 is an equidigital number, since it uses as much as digits as its factorization.

18955913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56586.

The product of its digits is 48600, while the sum is 41.

The square root of 18955913 is about 4353.8388808039. The cubic root of 18955913 is about 266.6336158691.

The spelling of 18955913 in words is "eighteen million, nine hundred fifty-five thousand, nine hundred thirteen".