209073844240 has 20 divisors (see below), whose sum is σ = 486096688044. Its totient is φ = 83629537664.

The previous prime is 209073844211. The next prime is 209073844247. The reversal of 209073844240 is 42448370902.

It can be written as a sum of positive squares in 2 ways, for example, as 36510037776 + 172563806464 = 191076^2 + 415408^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (209073844247) 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, 1306711447 + ... + 1306711606.

Almost surely, 2^209073844240 is an apocalyptic number.

209073844240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

209073844240 is an abundant number, since it is smaller than the sum of its proper divisors (277022843804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

209073844240 is a wasteful number, since it uses less digits than its factorization.

209073844240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2613423066 (or 2613423060 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 43.

The spelling of 209073844240 in words is "two hundred nine billion, seventy-three million, eight hundred forty-four thousand, two hundred forty".