159999 has 16 divisors (see below), whose sum is σ = 257280. Its totient is φ = 86400.

The previous prime is 159979. The next prime is 160001. The reversal of 159999 is 999951.

159999 = 16² + 17² + ... + 78².

It is a Cunningham number, because it is equal to 20⁴-1.

It is not a de Polignac number, because 159999 - 2⁷ = 159871 is a prime.

159999 is a modest number, since divided by 999 gives 159 as remainder.

159999 is a lucky number.

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 159999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (159979) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 199 + ... + 599.

It is an arithmetic number, because the mean of its divisors is an integer number (16080).

2¹⁵⁹⁹⁹⁹ is an apocalyptic number.

159999 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

159999 is a deficient number, since it is larger than the sum of its proper divisors (97281).

159999 is a wasteful number, since it uses less digits than its factorization.

159999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 430.

The product of its digits is 32805, while the sum is 42.

The square root of 159999 is about 399.9987499980. The cubic root of 159999 is about 54.2882392309.

The spelling of 159999 in words is "one hundred fifty-nine thousand, nine hundred ninety-nine".