159953991 has 8 divisors (see below), whose sum is σ = 216455424. Its totient is φ = 105044280.

The previous prime is 159953987. The next prime is 159954001. The reversal of 159953991 is 199359951.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 159953991 - 2² = 159953987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (159953921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 397695 + ... + 398096.

It is an arithmetic number, because the mean of its divisors is an integer number (27056928).

Almost surely, 2^159953991 is an apocalyptic number.

159953991 is a deficient number, since it is larger than the sum of its proper divisors (56501433).

159953991 is an equidigital number, since it uses as much as digits as its factorization.

159953991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 795861.

The product of its digits is 492075, while the sum is 51.

The square root of 159953991 is about 12647.2918445017. The cubic root of 159953991 is about 542.8314818137.

The spelling of 159953991 in words is "one hundred fifty-nine million, nine hundred fifty-three thousand, nine hundred ninety-one".