18240473 has 4 divisors (see below), whose sum is σ = 19313460. Its totient is φ = 17167488.

The previous prime is 18240463. The next prime is 18240479. The reversal of 18240473 is 37404281.

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 13630864 + 4609609 = 3692^2 + 2147^2 .

It is a cyclic number.

It is not a de Polignac number, because 18240473 - 2¹⁸ = 17978329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18240479) 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 3 ways as a sum of consecutive naturals, for example, 536468 + ... + 536501.

It is an arithmetic number, because the mean of its divisors is an integer number (4828365).

Almost surely, 2^18240473 is an apocalyptic number.

It is an amenable number.

18240473 is a deficient number, since it is larger than the sum of its proper divisors (1072987).

18240473 is a wasteful number, since it uses less digits than its factorization.

18240473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1072986.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 18240473 is about 4270.8866760896. The cubic root of 18240473 is about 263.2360499843.

The spelling of 18240473 in words is "eighteen million, two hundred forty thousand, four hundred seventy-three".