18240566 has 4 divisors (see below), whose sum is σ = 27360852. Its totient is φ = 9120282.

The previous prime is 18240529. The next prime is 18240577. The reversal of 18240566 is 66504281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 66504281 = 37 ⋅1797413.

It is a congruent number.

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 as a sum of consecutive naturals, namely, 4560140 + ... + 4560143.

It is an arithmetic number, because the mean of its divisors is an integer number (6840213).

Almost surely, 2^18240566 is an apocalyptic number.

18240566 is a deficient number, since it is larger than the sum of its proper divisors (9120286).

18240566 is an equidigital number, since it uses as much as digits as its factorization.

18240566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9120285.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 18240566 is about 4270.8975637447. The cubic root of 18240566 is about 263.2364973577.

The spelling of 18240566 in words is "eighteen million, two hundred forty thousand, five hundred sixty-six".