159617321 has 2 divisors, whose sum is σ = 159617322. Its totient is φ = 159617320.

The previous prime is 159617299. The next prime is 159617323. The reversal of 159617321 is 123716951.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 96255721 + 63361600 = 9811^2 + 7960^2 .

It is a cyclic number.

It is not a de Polignac number, because 159617321 - 2⁶ = 159617257 is a prime.

Together with 159617323, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (159617323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79808660 + 79808661.

It is an arithmetic number, because the mean of its divisors is an integer number (79808661).

Almost surely, 2^159617321 is an apocalyptic number.

It is an amenable number.

159617321 is a deficient number, since it is larger than the sum of its proper divisors (1).

159617321 is an equidigital number, since it uses as much as digits as its factorization.

159617321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11340, while the sum is 35.

The square root of 159617321 is about 12633.9748693750. The cubic root of 159617321 is about 542.4503650427.

The spelling of 159617321 in words is "one hundred fifty-nine million, six hundred seventeen thousand, three hundred twenty-one".