18172007 has 4 divisors (see below), whose sum is σ = 20768016. Its totient is φ = 15576000.

The previous prime is 18171991. The next prime is 18172019. The reversal of 18172007 is 70027181.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18172007 - 2⁴ = 18171991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18172097) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 1297994 + ... + 1298007.

It is an arithmetic number, because the mean of its divisors is an integer number (5192004).

Almost surely, 2^18172007 is an apocalyptic number.

18172007 is a deficient number, since it is larger than the sum of its proper divisors (2596009).

18172007 is an equidigital number, since it uses as much as digits as its factorization.

18172007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2596008.

The product of its (nonzero) digits is 784, while the sum is 26.

The square root of 18172007 is about 4262.8637088230. The cubic root of 18172007 is about 262.9062830224.

Adding to 18172007 its reverse (70027181), we get a palindrome (88199188).

The spelling of 18172007 in words is "eighteen million, one hundred seventy-two thousand, seven".