161555099 has 2 divisors, whose sum is σ = 161555100. Its totient is φ = 161555098.

The previous prime is 161555071. The next prime is 161555111. The reversal of 161555099 is 990555161.

It is a strong prime.

It is an emirp because it is prime and its reverse (990555161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161555099 - 2²⁴ = 144777883 is a prime.

It is a super-2 number, since 2×161555099² = 52200100025799602, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161555699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80777549 + 80777550.

It is an arithmetic number, because the mean of its divisors is an integer number (80777550).

Almost surely, 2^161555099 is an apocalyptic number.

161555099 is a deficient number, since it is larger than the sum of its proper divisors (1).

161555099 is an equidigital number, since it uses as much as digits as its factorization.

161555099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60750, while the sum is 41.

The square root of 161555099 is about 12710.4326834298. The cubic root of 161555099 is about 544.6366840394.

The spelling of 161555099 in words is "one hundred sixty-one million, five hundred fifty-five thousand, ninety-nine".