18115898 has 4 divisors (see below), whose sum is σ = 27173850. Its totient is φ = 9057948.

The previous prime is 18115883. The next prime is 18115901. The reversal of 18115898 is 89851181.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 89851181 = 7 ⋅12835883.

It can be written as a sum of positive squares in only one way, i.e., 18088009 + 27889 = 4253^2 + 167^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4528973 + ... + 4528976.

Almost surely, 2^18115898 is an apocalyptic number.

18115898 is a deficient number, since it is larger than the sum of its proper divisors (9057952).

18115898 is an equidigital number, since it uses as much as digits as its factorization.

18115898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9057951.

The product of its digits is 23040, while the sum is 41.

The square root of 18115898 is about 4256.2774815559. The cubic root of 18115898 is about 262.6354155433.

The spelling of 18115898 in words is "eighteen million, one hundred fifteen thousand, eight hundred ninety-eight".