161311409269 has 2 divisors, whose sum is σ = 161311409270. Its totient is φ = 161311409268.

The previous prime is 161311409263. The next prime is 161311409299. The reversal of 161311409269 is 962904113161.

161311409269 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90947480625 + 70363928644 = 301575^2 + 265262^2 .

It is a cyclic number.

It is not a de Polignac number, because 161311409269 - 2⁹ = 161311408757 is a prime.

It is a super-2 number, since 2×161311409269² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161311409263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80655704634 + 80655704635.

It is an arithmetic number, because the mean of its divisors is an integer number (80655704635).

Almost surely, 2^161311409269 is an apocalyptic number.

It is an amenable number.

161311409269 is a deficient number, since it is larger than the sum of its proper divisors (1).

161311409269 is an equidigital number, since it uses as much as digits as its factorization.

161311409269 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69984, while the sum is 43.

The spelling of 161311409269 in words is "one hundred sixty-one billion, three hundred eleven million, four hundred nine thousand, two hundred sixty-nine".