209698405255089 has 27 divisors (see below), whose sum is σ = 304174935211329. Its totient is φ = 139211907396480.

The previous prime is 209698405255069. The next prime is 209698405255133. The reversal of 209698405255089 is 980552504896902.

The square root of 209698405255089 is 14480967.

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

209698405255089 is a `hidden beast` number, since 2 + 0 + 9 + 6 + 9 + 8 + 40 + 525 + 50 + 8 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 45960070689 + 209652445184400 = 214383^2 + 14479380^2 .

It is not a de Polignac number, because 209698405255089 - 2²³ = 209698396866481 is a prime.

It is not an unprimeable number, because it can be changed into a prime (209698405255019) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 10469729127 + ... + 10469749155.

Almost surely, 2^{209698405255089} is an apocalyptic number.

209698405255089 is the 14480967-th square number.

209698405255089 is the 7240484-th centered octagonal number.

It is an amenable number.

209698405255089 is a deficient number, since it is larger than the sum of its proper divisors (94476529956240).

209698405255089 is an frugal number, since it uses more digits than its factorization.

209698405255089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40546 (or 20273 counting only the distinct ones).

The product of its (nonzero) digits is 559872000, while the sum is 72.

The spelling of 209698405255089 in words is "two hundred nine trillion, six hundred ninety-eight billion, four hundred five million, two hundred fifty-five thousand, eighty-nine".