161878099 has 2 divisors, whose sum is σ = 161878100. Its totient is φ = 161878098.

The previous prime is 161878091. The next prime is 161878103. The reversal of 161878099 is 990878161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161878099 - 2³ = 161878091 is a prime.

It is not a weakly prime, because it can be changed into another prime (161878091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80939049 + 80939050.

It is an arithmetic number, because the mean of its divisors is an integer number (80939050).

Almost surely, 2^161878099 is an apocalyptic number.

161878099 is a deficient number, since it is larger than the sum of its proper divisors (1).

161878099 is an equidigital number, since it uses as much as digits as its factorization.

161878099 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 217728, while the sum is 49.

The square root of 161878099 is about 12723.1324366290. The cubic root of 161878099 is about 544.9994097011. Note that the first 3 decimals are identical.

The spelling of 161878099 in words is "one hundred sixty-one million, eight hundred seventy-eight thousand, ninety-nine".