159520991 has 4 divisors (see below), whose sum is σ = 182309712. Its totient is φ = 136732272.

The previous prime is 159520981. The next prime is 159520993. The reversal of 159520991 is 199025951.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 199025951 = 307 ⋅648293.

It is a cyclic number.

It is not a de Polignac number, because 159520991 - 2¹⁴ = 159504607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (159520993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11394350 + ... + 11394363.

It is an arithmetic number, because the mean of its divisors is an integer number (45577428).

Almost surely, 2^159520991 is an apocalyptic number.

159520991 is a deficient number, since it is larger than the sum of its proper divisors (22788721).

159520991 is an equidigital number, since it uses as much as digits as its factorization.

159520991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22788720.

The product of its (nonzero) digits is 36450, while the sum is 41.

The square root of 159520991 is about 12630.1619546228. The cubic root of 159520991 is about 542.3412190787.

The spelling of 159520991 in words is "one hundred fifty-nine million, five hundred twenty thousand, nine hundred ninety-one".