18400005 has 48 divisors (see below), whose sum is σ = 34909056. Its totient is φ = 8910720.

The previous prime is 18400003. The next prime is 18400013. The reversal of 18400005 is 50000481.

It is not a de Polignac number, because 18400005 - 2¹ = 18400003 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18400003) 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, 41314 + ... + 41756.

It is an arithmetic number, because the mean of its divisors is an integer number (727272).

Almost surely, 2^18400005 is an apocalyptic number.

18400005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18400005 is a deficient number, since it is larger than the sum of its proper divisors (16509051).

18400005 is a wasteful number, since it uses less digits than its factorization.

18400005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538 (or 535 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 18400005 is about 4289.5227007209. The cubic root of 18400005 is about 264.0012482723.

Adding to 18400005 its reverse (50000481), we get a palindrome (68400486).

The spelling of 18400005 in words is "eighteen million, four hundred thousand, five".