159171921 has 6 divisors (see below), whose sum is σ = 229915010. Its totient is φ = 106114608.

The previous prime is 159171919. The next prime is 159171931. The reversal of 159171921 is 129171951.

159171921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 106812225 + 52359696 = 10335^2 + 7236^2 .

It is not a de Polignac number, because 159171921 - 2¹ = 159171919 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (159171931) 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, 8842876 + ... + 8842893.

Almost surely, 2^159171921 is an apocalyptic number.

It is an amenable number.

159171921 is a deficient number, since it is larger than the sum of its proper divisors (70743089).

159171921 is a wasteful number, since it uses less digits than its factorization.

159171921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17685775 (or 17685772 counting only the distinct ones).

The product of its digits is 5670, while the sum is 36.

The square root of 159171921 is about 12616.3354822230. The cubic root of 159171921 is about 541.9453395039.

The spelling of 159171921 in words is "one hundred fifty-nine million, one hundred seventy-one thousand, nine hundred twenty-one".