161998229 has 2 divisors, whose sum is σ = 161998230. Its totient is φ = 161998228.

The previous prime is 161998211. The next prime is 161998267. The reversal of 161998229 is 922899161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 145757329 + 16240900 = 12073^2 + 4030^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161998229 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161998289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80999114 + 80999115.

It is an arithmetic number, because the mean of its divisors is an integer number (80999115).

Almost surely, 2^161998229 is an apocalyptic number.

It is an amenable number.

161998229 is a deficient number, since it is larger than the sum of its proper divisors (1).

161998229 is an equidigital number, since it uses as much as digits as its factorization.

161998229 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 47.

The square root of 161998229 is about 12727.8524897172. The cubic root of 161998229 is about 545.1341913482.

The spelling of 161998229 in words is "one hundred sixty-one million, nine hundred ninety-eight thousand, two hundred twenty-nine".