18021711 has 8 divisors (see below), whose sum is σ = 24048640. Its totient is φ = 12004632.

The previous prime is 18021691. The next prime is 18021713. The reversal of 18021711 is 11712081.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-18021711 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 (18021713) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5376 + ... + 8058.

It is an arithmetic number, because the mean of its divisors is an integer number (3006080).

Almost surely, 2^18021711 is an apocalyptic number.

18021711 is a deficient number, since it is larger than the sum of its proper divisors (6026929).

18021711 is a wasteful number, since it uses less digits than its factorization.

18021711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4925.

The product of its (nonzero) digits is 112, while the sum is 21.

The square root of 18021711 is about 4245.1985819276. The cubic root of 18021711 is about 262.1794654490.

Adding to 18021711 its reverse (11712081), we get a palindrome (29733792).

The spelling of 18021711 in words is "eighteen million, twenty-one thousand, seven hundred eleven".