159398665 has 4 divisors (see below), whose sum is σ = 191278404. Its totient is φ = 127518928.

The previous prime is 159398663. The next prime is 159398699. The reversal of 159398665 is 566893951.

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 76370121 + 83028544 = 8739^2 + 9112^2 .

It is a cyclic number.

It is not a de Polignac number, because 159398665 - 2¹ = 159398663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (159398663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15939862 + ... + 15939871.

It is an arithmetic number, because the mean of its divisors is an integer number (47819601).

Almost surely, 2^159398665 is an apocalyptic number.

It is an amenable number.

159398665 is a deficient number, since it is larger than the sum of its proper divisors (31879739).

159398665 is an equidigital number, since it uses as much as digits as its factorization.

159398665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31879738.

The product of its digits is 1749600, while the sum is 52.

The square root of 159398665 is about 12625.3184118263. The cubic root of 159398665 is about 542.2025552021.

The spelling of 159398665 in words is "one hundred fifty-nine million, three hundred ninety-eight thousand, six hundred sixty-five".