161289899 has 2 divisors, whose sum is σ = 161289900. Its totient is φ = 161289898.

The previous prime is 161289889. The next prime is 161289911. The reversal of 161289899 is 998982161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161289899 - 2⁴ = 161289883 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 161289899.

It is not a weakly prime, because it can be changed into another prime (161289889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80644949 + 80644950.

It is an arithmetic number, because the mean of its divisors is an integer number (80644950).

Almost surely, 2^161289899 is an apocalyptic number.

161289899 is a deficient number, since it is larger than the sum of its proper divisors (1).

161289899 is an equidigital number, since it uses as much as digits as its factorization.

161289899 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 559872, while the sum is 53.

The square root of 161289899 is about 12699.9960236214. The cubic root of 161289899 is about 544.3385055742.

The spelling of 161289899 in words is "one hundred sixty-one million, two hundred eighty-nine thousand, eight hundred ninety-nine".