209492036209 has 9 divisors (see below), whose sum is σ = 210751342347. Its totient is φ = 208240218504.

The previous prime is 209492036197. The next prime is 209492036213. The reversal of 209492036209 is 902630294902.

The square root of 209492036209 is 457703.

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

It can be written as a sum of positive squares in only one way, i.e., 89895030625 + 119597005584 = 299825^2 + 345828^2 .

It is not a de Polignac number, because 209492036209 - 2²⁹ = 208955165297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (209492036239) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 81927559 + ... + 81930115.

Almost surely, 2^209492036209 is an apocalyptic number.

209492036209 is the 457703-rd square number.

209492036209 is the 228852-nd centered octagonal number.

It is an amenable number.

209492036209 is a deficient number, since it is larger than the sum of its proper divisors (1259306138).

209492036209 is an frugal number, since it uses more digits than its factorization.

209492036209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5472 (or 2736 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 46.

The spelling of 209492036209 in words is "two hundred nine billion, four hundred ninety-two million, thirty-six thousand, two hundred nine".