135941902209 has 45 divisors (see below), whose sum is σ = 206331776211. Its totient is φ = 89196629760.

The previous prime is 135941902163. The next prime is 135941902219. The reversal of 135941902209 is 902209149531.

The square root of 135941902209 is 368703.

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

135941902209 is a `hidden beast` number, since 1 + 3 + 5 + 9 + 419 + 0 + 220 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 135001130625 + 940771584 = 367425^2 + 30672^2 .

It is not a de Polignac number, because 135941902209 - 2¹⁷ = 135941771137 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (135941902219) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 235600929 + ... + 235601505.

Almost surely, 2^135941902209 is an apocalyptic number.

135941902209 is the 368703-rd square number.

135941902209 is the 184352-nd centered octagonal number.

It is an amenable number.

135941902209 is a deficient number, since it is larger than the sum of its proper divisors (70389874002).

135941902209 is an frugal number, since it uses more digits than its factorization.

135941902209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1308 (or 651 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 45.

The spelling of 135941902209 in words is "one hundred thirty-five billion, nine hundred forty-one million, nine hundred two thousand, two hundred nine".