3861409712209 has 63 divisors (see below), whose sum is σ = 4799801661393. Its totient is φ = 3105843245568.

The previous prime is 3861409712207. The next prime is 3861409712267. The reversal of 3861409712209 is 9022179041683.

The square root of 3861409712209 is 1965047.

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

It can be written as a sum of positive squares in 4 ways, for example, as 12122670609 + 3849287041600 = 110103^2 + 1961960^2 .

It is not a de Polignac number, because 3861409712209 - 2¹ = 3861409712207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3861409712207) by changing a digit.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 11458188889 + ... + 11458189225.

Almost surely, 2^{3861409712209} is an apocalyptic number.

3861409712209 is the 1965047-th square number.

3861409712209 is the 982524-th centered octagonal number.

It is an amenable number.

3861409712209 is a deficient number, since it is larger than the sum of its proper divisors (938391949184).

3861409712209 is an frugal number, since it uses more digits than its factorization.

3861409712209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 750 (or 361 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 52.

The spelling of 3861409712209 in words is "three trillion, eight hundred sixty-one billion, four hundred nine million, seven hundred twelve thousand, two hundred nine".