18905013 has 24 divisors (see below), whose sum is σ = 28543320. Its totient is φ = 12042240.

The previous prime is 18904997. The next prime is 18905017. The reversal of 18905013 is 31050981.

It can be written as a sum of positive squares in 4 ways, for example, as 1790244 + 17114769 = 1338^2 + 4137^2 .

It is not a de Polignac number, because 18905013 - 2⁴ = 18904997 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18905017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 29173 + ... + 29813.

It is an arithmetic number, because the mean of its divisors is an integer number (1189305).

Almost surely, 2^18905013 is an apocalyptic number.

It is an amenable number.

18905013 is a deficient number, since it is larger than the sum of its proper divisors (9638307).

18905013 is a wasteful number, since it uses less digits than its factorization.

18905013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 789 (or 786 counting only the distinct ones).

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

The square root of 18905013 is about 4347.9895354060. The cubic root of 18905013 is about 266.3947490375.

Adding to 18905013 its reverse (31050981), we get a palindrome (49955994).

It can be divided in two parts, 1890 and 5013, that added together give a triangular number (6903 = T₁₁₇).

The spelling of 18905013 in words is "eighteen million, nine hundred five thousand, thirteen".