161872177 has 2 divisors, whose sum is σ = 161872178. Its totient is φ = 161872176.

The previous prime is 161872169. The next prime is 161872187. The reversal of 161872177 is 771278161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 160757041 + 1115136 = 12679^2 + 1056^2 .

It is an emirp because it is prime and its reverse (771278161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161872177 - 2³ = 161872169 is a prime.

It is not a weakly prime, because it can be changed into another prime (161872127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80936088 + 80936089.

It is an arithmetic number, because the mean of its divisors is an integer number (80936089).

Almost surely, 2^161872177 is an apocalyptic number.

It is an amenable number.

161872177 is a deficient number, since it is larger than the sum of its proper divisors (1).

161872177 is an equidigital number, since it uses as much as digits as its factorization.

161872177 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32928, while the sum is 40.

The square root of 161872177 is about 12722.8997087928. The cubic root of 161872177 is about 544.9927637005.

The spelling of 161872177 in words is "one hundred sixty-one million, eight hundred seventy-two thousand, one hundred seventy-seven".