18408536309 has 8 divisors (see below), whose sum is σ = 19495102680. Its totient is φ = 17322382336.

The previous prime is 18408536303. The next prime is 18408536323. The reversal of 18408536309 is 90363580481.

It can be written as a sum of positive squares in 4 ways, for example, as 11191524100 + 7217012209 = 105790^2 + 84953^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 18408536309 - 2³² = 14113569013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18408536303) 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, 8714 + ... + 192075.

It is an arithmetic number, because the mean of its divisors is an integer number (2436887835).

Almost surely, 2^18408536309 is an apocalyptic number.

It is an amenable number.

18408536309 is a deficient number, since it is larger than the sum of its proper divisors (1086566371).

18408536309 is a wasteful number, since it uses less digits than its factorization.

18408536309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206199.

The product of its (nonzero) digits is 622080, while the sum is 47.

The spelling of 18408536309 in words is "eighteen billion, four hundred eight million, five hundred thirty-six thousand, three hundred nine".