209009225098081 has 16 divisors (see below), whose sum is σ = 211479435072720. Its totient is φ = 206541750159360.

The previous prime is 209009225098073. The next prime is 209009225098099. The reversal of 209009225098081 is 180890522900902.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 37191763235025 + 171817461863056 = 6098505^2 + 13107916^2 .

It is a cyclic number.

It is not a de Polignac number, because 209009225098081 - 2³ = 209009225098073 is a prime.

It is a super-2 number, since 2×209009225098081² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209009225098381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1361360601 + ... + 1361514121.

It is an arithmetic number, because the mean of its divisors is an integer number (13217464692045).

Almost surely, 2^{209009225098081} is an apocalyptic number.

It is an amenable number.

209009225098081 is a deficient number, since it is larger than the sum of its proper divisors (2470209974639).

209009225098081 is a wasteful number, since it uses less digits than its factorization.

209009225098081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162324.

The product of its (nonzero) digits is 1866240, while the sum is 55.

Adding to 209009225098081 its reverse (180890522900902), we get a palindrome (389899747998983).

The spelling of 209009225098081 in words is "two hundred nine trillion, nine billion, two hundred twenty-five million, ninety-eight thousand, eighty-one".