161775385 has 4 divisors (see below), whose sum is σ = 194130468. Its totient is φ = 129420304.

The previous prime is 161775343. The next prime is 161775401. The reversal of 161775385 is 583577161.

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 119836809 + 41938576 = 10947^2 + 6476^2 .

It is a cyclic number.

It is not a de Polignac number, because 161775385 - 2¹⁵ = 161742617 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16177534 + ... + 16177543.

It is an arithmetic number, because the mean of its divisors is an integer number (48532617).

Almost surely, 2^161775385 is an apocalyptic number.

It is an amenable number.

161775385 is a deficient number, since it is larger than the sum of its proper divisors (32355083).

161775385 is an equidigital number, since it uses as much as digits as its factorization.

161775385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32355082.

The product of its digits is 176400, while the sum is 43.

The square root of 161775385 is about 12719.0952901533. The cubic root of 161775385 is about 544.8841153042.

The spelling of 161775385 in words is "one hundred sixty-one million, seven hundred seventy-five thousand, three hundred eighty-five".