161165665 has 8 divisors (see below), whose sum is σ = 195729408. Its totient is φ = 127378800.

The previous prime is 161165663. The next prime is 161165671. The reversal of 161165665 is 566561161.

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

It is not a de Polignac number, because 161165665 - 2¹ = 161165663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161165663) by changing a digit.

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, 193761 + ... + 194590.

It is an arithmetic number, because the mean of its divisors is an integer number (24466176).

Almost surely, 2^161165665 is an apocalyptic number.

It is an amenable number.

161165665 is a deficient number, since it is larger than the sum of its proper divisors (34563743).

161165665 is an equidigital number, since it uses as much as digits as its factorization.

161165665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 388439.

The product of its digits is 32400, while the sum is 37.

The square root of 161165665 is about 12695.1039775183. The cubic root of 161165665 is about 544.1987102520.

It can be divided in two parts, 1611 and 65665, that added together give a palindrome (67276).

The spelling of 161165665 in words is "one hundred sixty-one million, one hundred sixty-five thousand, six hundred sixty-five".