159991855 has 4 divisors (see below), whose sum is σ = 191990232. Its totient is φ = 127993480.

The previous prime is 159991849. The next prime is 159991861. The reversal of 159991855 is 558199951.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (159991849) and next prime (159991861).

It is a de Polignac number, because none of the positive numbers 2^k-159991855 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15999181 + ... + 15999190.

It is an arithmetic number, because the mean of its divisors is an integer number (47997558).

Almost surely, 2^159991855 is an apocalyptic number.

159991855 is a deficient number, since it is larger than the sum of its proper divisors (31998377).

159991855 is an equidigital number, since it uses as much as digits as its factorization.

159991855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31998376.

The product of its digits is 729000, while the sum is 52.

The square root of 159991855 is about 12648.7886771817. The cubic root of 159991855 is about 542.8743111079.

The spelling of 159991855 in words is "one hundred fifty-nine million, nine hundred ninety-one thousand, eight hundred fifty-five".