18316649 has 8 divisors (see below), whose sum is σ = 19996872. Its totient is φ = 16675200.

The previous prime is 18316643. The next prime is 18316673. The reversal of 18316649 is 94661381.

It can be written as a sum of positive squares in 4 ways, for example, as 1243225 + 17073424 = 1115^2 + 4132^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18316649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18316643) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8702 + ... + 10599.

It is an arithmetic number, because the mean of its divisors is an integer number (2499609).

Almost surely, 2^18316649 is an apocalyptic number.

It is an amenable number.

18316649 is a deficient number, since it is larger than the sum of its proper divisors (1680223).

18316649 is a wasteful number, since it uses less digits than its factorization.

18316649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19387.

The product of its digits is 31104, while the sum is 38.

The square root of 18316649 is about 4279.7954390368. The cubic root of 18316649 is about 263.6019838388.

The spelling of 18316649 in words is "eighteen million, three hundred sixteen thousand, six hundred forty-nine".