161271205 has 4 divisors (see below), whose sum is σ = 193525452. Its totient is φ = 129016960.

The previous prime is 161271203. The next prime is 161271217. The reversal of 161271205 is 502172161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35450116 + 125821089 = 5954^2 + 11217^2 .

It is not a de Polignac number, because 161271205 - 2¹ = 161271203 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161271205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161271203) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16127116 + ... + 16127125.

It is an arithmetic number, because the mean of its divisors is an integer number (48381363).

Almost surely, 2^161271205 is an apocalyptic number.

It is an amenable number.

161271205 is a deficient number, since it is larger than the sum of its proper divisors (32254247).

161271205 is an equidigital number, since it uses as much as digits as its factorization.

161271205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32254246.

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 161271205 is about 12699.2600178121. The cubic root of 161271205 is about 544.3174745875.

The spelling of 161271205 in words is "one hundred sixty-one million, two hundred seventy-one thousand, two hundred five".