159021993 has 16 divisors (see below), whose sum is σ = 236214720. Its totient is φ = 94484544.

The previous prime is 159021991. The next prime is 159022013. The reversal of 159021993 is 399120951.

It is not a de Polignac number, because 159021993 - 2¹ = 159021991 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (159021991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69171 + ... + 71432.

It is an arithmetic number, because the mean of its divisors is an integer number (14763420).

Almost surely, 2^159021993 is an apocalyptic number.

159021993 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

159021993 is a deficient number, since it is larger than the sum of its proper divisors (77192727).

159021993 is a wasteful number, since it uses less digits than its factorization.

159021993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140648.

The product of its (nonzero) digits is 21870, while the sum is 39.

The square root of 159021993 is about 12610.3922619401. The cubic root of 159021993 is about 541.7751287761.

The spelling of 159021993 in words is "one hundred fifty-nine million, twenty-one thousand, nine hundred ninety-three".