161145505 has 8 divisors (see below), whose sum is σ = 196098624. Its totient is φ = 127100400.

The previous prime is 161145497. The next prime is 161145617. The reversal of 161145505 is 505541161.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161145505 - 2³ = 161145497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 226611 + ... + 227320.

It is an arithmetic number, because the mean of its divisors is an integer number (24512328).

Almost surely, 2^161145505 is an apocalyptic number.

It is an amenable number.

161145505 is a deficient number, since it is larger than the sum of its proper divisors (34953119).

161145505 is an equidigital number, since it uses as much as digits as its factorization.

161145505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 454007.

The product of its (nonzero) digits is 3000, while the sum is 28.

The square root of 161145505 is about 12694.3099457986. The cubic root of 161145505 is about 544.1760182733.

Adding to 161145505 its reverse (505541161), we get a palindrome (666686666).

The spelling of 161145505 in words is "one hundred sixty-one million, one hundred forty-five thousand, five hundred five".