1565540161 has 8 divisors (see below), whose sum is σ = 1592712000. Its totient is φ = 1538389680.

The previous prime is 1565540143. The next prime is 1565540191. The reversal of 1565540161 is 1610455651.

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

It is a cyclic number.

It is not a de Polignac number, because 1565540161 - 2⁷ = 1565540033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1565540191) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 233940 + ... + 240538.

It is an arithmetic number, because the mean of its divisors is an integer number (199089000).

Almost surely, 2^1565540161 is an apocalyptic number.

It is an amenable number.

1565540161 is a deficient number, since it is larger than the sum of its proper divisors (27171839).

1565540161 is an equidigital number, since it uses as much as digits as its factorization.

1565540161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10679.

The product of its (nonzero) digits is 18000, while the sum is 34.

The square root of 1565540161 is about 39566.9073974704. The cubic root of 1565540161 is about 1161.1493169459.

The spelling of 1565540161 in words is "one billion, five hundred sixty-five million, five hundred forty thousand, one hundred sixty-one".