18120289 has 4 divisors (see below), whose sum is σ = 19767600. Its totient is φ = 16472980.

The previous prime is 18120287. The next prime is 18120307. The reversal of 18120289 is 98202181.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18120289 - 2¹ = 18120287 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18120289.

It is not an unprimeable number, because it can be changed into a prime (18120287) 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, 823639 + ... + 823660.

It is an arithmetic number, because the mean of its divisors is an integer number (4941900).

Almost surely, 2^18120289 is an apocalyptic number.

It is an amenable number.

18120289 is a deficient number, since it is larger than the sum of its proper divisors (1647311).

18120289 is a wasteful number, since it uses less digits than its factorization.

18120289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1647310.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 18120289 is about 4256.7932766344. The cubic root of 18120289 is about 262.6566333515.

The spelling of 18120289 in words is "eighteen million, one hundred twenty thousand, two hundred eighty-nine".