18198449 has 4 divisors (see below), whose sum is σ = 19268964. Its totient is φ = 17127936.

The previous prime is 18198431. The next prime is 18198469. The reversal of 18198449 is 94489181.

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 5094049 + 13104400 = 2257^2 + 3620^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18198449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18198469) 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, 535232 + ... + 535265.

It is an arithmetic number, because the mean of its divisors is an integer number (4817241).

Almost surely, 2^18198449 is an apocalyptic number.

It is an amenable number.

18198449 is a deficient number, since it is larger than the sum of its proper divisors (1070515).

18198449 is a wasteful number, since it uses less digits than its factorization.

18198449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1070514.

The product of its digits is 82944, while the sum is 44.

The square root of 18198449 is about 4265.9640176635. The cubic root of 18198449 is about 263.0337391116.

The spelling of 18198449 in words is "eighteen million, one hundred ninety-eight thousand, four hundred forty-nine".