159021 has 6 divisors (see below), whose sum is σ = 229710. Its totient is φ = 106008.

The previous prime is 159017. The next prime is 159023. The reversal of 159021 is 120951.

It can be written as a sum of positive squares in only one way, i.e., 114921 + 44100 = 339^2 + 210^2 .

It is not a de Polignac number, because 159021 - 2² = 159017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 158985 and 159003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (159023) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8826 + ... + 8843.

It is an arithmetic number, because the mean of its divisors is an integer number (38285).

2¹⁵⁹⁰²¹ is an apocalyptic number.

It is an amenable number.

159021 is a deficient number, since it is larger than the sum of its proper divisors (70689).

159021 is a wasteful number, since it uses less digits than its factorization.

159021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17675 (or 17672 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 18.

The square root of 159021 is about 398.7743722959. The cubic root of 159021 is about 54.1774001083.

Adding to 159021 its reverse (120951), we get a palindrome (279972).

The spelling of 159021 in words is "one hundred fifty-nine thousand, twenty-one".