18001807 has 4 divisors (see below), whose sum is σ = 18019456. Its totient is φ = 17984160.

The previous prime is 18001729. The next prime is 18001811. The reversal of 18001807 is 70810081.

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 18001807 - 2¹⁹ = 17477519 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 (18001817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7194 + ... + 9367.

It is an arithmetic number, because the mean of its divisors is an integer number (4504864).

Almost surely, 2^18001807 is an apocalyptic number.

18001807 is a deficient number, since it is larger than the sum of its proper divisors (17649).

18001807 is a wasteful number, since it uses less digits than its factorization.

18001807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17648.

The product of its (nonzero) digits is 448, while the sum is 25.

The square root of 18001807 is about 4242.8536387672. The cubic root of 18001807 is about 262.0829089047.

Adding to 18001807 its reverse (70810081), we get a palindrome (88811888).

The spelling of 18001807 in words is "eighteen million, one thousand, eight hundred seven".