161890259 has 2 divisors, whose sum is σ = 161890260. Its totient is φ = 161890258.

The previous prime is 161890247. The next prime is 161890273. The reversal of 161890259 is 952098161.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161890259 - 2²⁴ = 145113043 is a prime.

It is not a weakly prime, because it can be changed into another prime (161890219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80945129 + 80945130.

It is an arithmetic number, because the mean of its divisors is an integer number (80945130).

Almost surely, 2^161890259 is an apocalyptic number.

161890259 is a deficient number, since it is larger than the sum of its proper divisors (1).

161890259 is an equidigital number, since it uses as much as digits as its factorization.

161890259 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 41.

The square root of 161890259 is about 12723.6102973959. The cubic root of 161890259 is about 545.0130558273.

The spelling of 161890259 in words is "one hundred sixty-one million, eight hundred ninety thousand, two hundred fifty-nine".