1209540218 has 8 divisors (see below), whose sum is σ = 1814674260. Its totient is φ = 604648800.

The previous prime is 1209540203. The next prime is 1209540229. The reversal of 1209540218 is 8120459021.

It can be written as a sum of positive squares in 2 ways, for example, as 1209439729 + 100489 = 34777^2 + 317^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47633 + ... + 68468.

Almost surely, 2^1209540218 is an apocalyptic number.

1209540218 is a deficient number, since it is larger than the sum of its proper divisors (605134042).

1209540218 is a wasteful number, since it uses less digits than its factorization.

1209540218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121312.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 1209540218 is about 34778.4447323338. Note that the first 3 decimals coincide. The cubic root of 1209540218 is about 1065.4672486680.

Adding to 1209540218 its reverse (8120459021), we get a palindrome (9329999239).

The spelling of 1209540218 in words is "one billion, two hundred nine million, five hundred forty thousand, two hundred eighteen".