209138722 has 32 divisors (see below), whose sum is σ = 344615040. Its totient is φ = 94608000.

The previous prime is 209138711. The next prime is 209138723. The reversal of 209138722 is 227831902.

It is not an unprimeable number, because it can be changed into a prime (209138723) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 476179 + ... + 476617.

It is an arithmetic number, because the mean of its divisors is an integer number (10769220).

Almost surely, 2^209138722 is an apocalyptic number.

209138722 is a deficient number, since it is larger than the sum of its proper divisors (135476318).

209138722 is a wasteful number, since it uses less digits than its factorization.

209138722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 209138722 is about 14461.6292996329. The cubic root of 209138722 is about 593.5784835410.

The spelling of 209138722 in words is "two hundred nine million, one hundred thirty-eight thousand, seven hundred twenty-two".