18289897 has 4 divisors (see below), whose sum is σ = 18326340. Its totient is φ = 18253456.

The previous prime is 18289879. The next prime is 18289903. The reversal of 18289897 is 79898281.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13980121 + 4309776 = 3739^2 + 2076^2 .

It is a cyclic number.

It is not a de Polignac number, because 18289897 - 2¹¹ = 18287849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18289867) 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, 17458 + ... + 18475.

It is an arithmetic number, because the mean of its divisors is an integer number (4581585).

Almost surely, 2^18289897 is an apocalyptic number.

It is an amenable number.

18289897 is a deficient number, since it is larger than the sum of its proper divisors (36443).

18289897 is an equidigital number, since it uses as much as digits as its factorization.

18289897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36442.

The product of its digits is 580608, while the sum is 52.

The square root of 18289897 is about 4276.6689140030. The cubic root of 18289897 is about 263.4735885154.

The spelling of 18289897 in words is "eighteen million, two hundred eighty-nine thousand, eight hundred ninety-seven".