161280005 has 4 divisors (see below), whose sum is σ = 193536012. Its totient is φ = 129024000.

The previous prime is 161279957. The next prime is 161280013. The reversal of 161280005 is 500082161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 500082161 = 1427 ⋅350443.

It can be written as a sum of positive squares in 2 ways, for example, as 21520321 + 139759684 = 4639^2 + 11822^2 .

It is not a de Polignac number, because 161280005 - 2⁶ = 161279941 is a prime.

It is a super-2 number, since 2×161280005² = 52022480025600050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16127996 + ... + 16128005.

It is an arithmetic number, because the mean of its divisors is an integer number (48384003).

Almost surely, 2^161280005 is an apocalyptic number.

It is an amenable number.

161280005 is a deficient number, since it is larger than the sum of its proper divisors (32256007).

161280005 is an equidigital number, since it uses as much as digits as its factorization.

161280005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32256006.

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 161280005 is about 12699.6064899665. The cubic root of 161280005 is about 544.3273749013.

The spelling of 161280005 in words is "one hundred sixty-one million, two hundred eighty thousand, five".