209291610256 has 15 divisors (see below), whose sum is σ = 405506040403. Its totient is φ = 104644890160.

The previous prime is 209291610181. The next prime is 209291610257. The reversal of 209291610256 is 652016192902.

The square root of 209291610256 is 457484.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209291610257) 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 2 ways as a sum of consecutive naturals, for example, 1772751 + ... + 1887121.

Almost surely, 2^209291610256 is an apocalyptic number.

209291610256 is the 457484-th square number.

It is an amenable number.

209291610256 is a deficient number, since it is larger than the sum of its proper divisors (196214430147).

209291610256 is an frugal number, since it uses more digits than its factorization.

209291610256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228750 (or 114373 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 43.

The spelling of 209291610256 in words is "two hundred nine billion, two hundred ninety-one million, six hundred ten thousand, two hundred fifty-six".