163405331261 has 2 divisors, whose sum is σ = 163405331262. Its totient is φ = 163405331260.

The previous prime is 163405331147. The next prime is 163405331279. The reversal of 163405331261 is 162133504361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 154051540036 + 9353791225 = 392494^2 + 96715^2 .

It is a cyclic number.

It is not a de Polignac number, because 163405331261 - 2³⁰ = 162331589437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (163405301261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81702665630 + 81702665631.

It is an arithmetic number, because the mean of its divisors is an integer number (81702665631).

Almost surely, 2^163405331261 is an apocalyptic number.

It is an amenable number.

163405331261 is a deficient number, since it is larger than the sum of its proper divisors (1).

163405331261 is an equidigital number, since it uses as much as digits as its factorization.

163405331261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 35.

The spelling of 163405331261 in words is "one hundred sixty-three billion, four hundred five million, three hundred thirty-one thousand, two hundred sixty-one".