209137090 has 8 divisors (see below), whose sum is σ = 376446780. Its totient is φ = 83654832.

The previous prime is 209137073. The next prime is 209137133. The reversal of 209137090 is 90731902.

It can be written as a sum of positive squares in 2 ways, for example, as 169182049 + 39955041 = 13007^2 + 6321^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10456845 + ... + 10456864.

Almost surely, 2^209137090 is an apocalyptic number.

209137090 is a deficient number, since it is larger than the sum of its proper divisors (167309690).

209137090 is a wasteful number, since it uses less digits than its factorization.

209137090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20913716.

The product of its (nonzero) digits is 3402, while the sum is 31.

The square root of 209137090 is about 14461.5728743453. The cubic root of 209137090 is about 593.5769395537.

Adding to 209137090 its reverse (90731902), we get a palindrome (299868992).

The spelling of 209137090 in words is "two hundred nine million, one hundred thirty-seven thousand, ninety".