161883391 has 2 divisors, whose sum is σ = 161883392. Its totient is φ = 161883390.

The previous prime is 161883383. The next prime is 161883419. The reversal of 161883391 is 193388161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161883391 - 2³ = 161883383 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161883311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80941695 + 80941696.

It is an arithmetic number, because the mean of its divisors is an integer number (80941696).

Almost surely, 2^161883391 is an apocalyptic number.

161883391 is a deficient number, since it is larger than the sum of its proper divisors (1).

161883391 is an equidigital number, since it uses as much as digits as its factorization.

161883391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 40.

The square root of 161883391 is about 12723.3404025830. The cubic root of 161883391 is about 545.0053485433.

The spelling of 161883391 in words is "one hundred sixty-one million, eight hundred eighty-three thousand, three hundred ninety-one".