1169388781261 has 2 divisors, whose sum is σ = 1169388781262. Its totient is φ = 1169388781260.

The previous prime is 1169388781207. The next prime is 1169388781279. The reversal of 1169388781261 is 1621878839611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 840980702500 + 328408078761 = 917050^2 + 573069^2 .

It is a cyclic number.

It is not a de Polignac number, because 1169388781261 - 2¹⁷ = 1169388650189 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1169388781261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1169388781361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 584694390630 + 584694390631.

It is an arithmetic number, because the mean of its divisors is an integer number (584694390631).

Almost surely, 2^{1169388781261} is an apocalyptic number.

It is an amenable number.

1169388781261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1169388781261 is an equidigital number, since it uses as much as digits as its factorization.

1169388781261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6967296, while the sum is 61.

The spelling of 1169388781261 in words is "one trillion, one hundred sixty-nine billion, three hundred eighty-eight million, seven hundred eighty-one thousand, two hundred sixty-one".