161081403709 has 2 divisors, whose sum is σ = 161081403710. Its totient is φ = 161081403708.

The previous prime is 161081403673. The next prime is 161081403731. The reversal of 161081403709 is 907304180161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117066622500 + 44014781209 = 342150^2 + 209797^2 .

It is a cyclic number.

It is not a de Polignac number, because 161081403709 - 2²³ = 161073015101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161081403809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80540701854 + 80540701855.

It is an arithmetic number, because the mean of its divisors is an integer number (80540701855).

Almost surely, 2^161081403709 is an apocalyptic number.

It is an amenable number.

161081403709 is a deficient number, since it is larger than the sum of its proper divisors (1).

161081403709 is an equidigital number, since it uses as much as digits as its factorization.

161081403709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 40.

The spelling of 161081403709 in words is "one hundred sixty-one billion, eighty-one million, four hundred three thousand, seven hundred nine".