161940277 has 2 divisors, whose sum is σ = 161940278. Its totient is φ = 161940276.

The previous prime is 161940223. The next prime is 161940293. The reversal of 161940277 is 772049161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 109537156 + 52403121 = 10466^2 + 7239^2 .

It is a cyclic number.

It is not a de Polignac number, because 161940277 - 2¹⁵ = 161907509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161940377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80970138 + 80970139.

It is an arithmetic number, because the mean of its divisors is an integer number (80970139).

Almost surely, 2^161940277 is an apocalyptic number.

It is an amenable number.

161940277 is a deficient number, since it is larger than the sum of its proper divisors (1).

161940277 is an equidigital number, since it uses as much as digits as its factorization.

161940277 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 161940277 is about 12725.5757040693. The cubic root of 161940277 is about 545.0691795582.

The spelling of 161940277 in words is "one hundred sixty-one million, nine hundred forty thousand, two hundred seventy-seven".