159820165 has 4 divisors (see below), whose sum is σ = 191784204. Its totient is φ = 127856128.

The previous prime is 159820147. The next prime is 159820181. The reversal of 159820165 is 561028951.

It is a Cunningham number, because it is equal to 12642²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 57547396 + 102272769 = 7586^2 + 10113^2 .

It is a cyclic number.

It is not a de Polignac number, because 159820165 - 2¹¹ = 159818117 is a prime.

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, 15982012 + ... + 15982021.

It is an arithmetic number, because the mean of its divisors is an integer number (47946051).

Almost surely, 2^159820165 is an apocalyptic number.

It is an amenable number.

159820165 is a deficient number, since it is larger than the sum of its proper divisors (31964039).

159820165 is an equidigital number, since it uses as much as digits as its factorization.

159820165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31964038.

The product of its (nonzero) digits is 21600, while the sum is 37.

The square root of 159820165 is about 12642.0000395507. Note that the first 4 decimals coincide. The cubic root of 159820165 is about 542.6800523632.

The spelling of 159820165 in words is "one hundred fifty-nine million, eight hundred twenty thousand, one hundred sixty-five".