18240705 has 48 divisors (see below), whose sum is σ = 36641280. Its totient is φ = 8221824.

The previous prime is 18240689. The next prime is 18240707. The reversal of 18240705 is 50704281.

It is not a de Polignac number, because 18240705 - 2⁴ = 18240689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18240707) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 24519 + ... + 25251.

It is an arithmetic number, because the mean of its divisors is an integer number (763360).

Almost surely, 2^18240705 is an apocalyptic number.

18240705 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18240705 is an abundant number, since it is smaller than the sum of its proper divisors (18400575).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18240705 is a wasteful number, since it uses less digits than its factorization.

18240705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 830 (or 827 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 18240705 is about 4270.9138366396. The cubic root of 18240705 is about 263.2371660099.

Adding to 18240705 its reverse (50704281), we get a palindrome (68944986).

The spelling of 18240705 in words is "eighteen million, two hundred forty thousand, seven hundred five".