159472721 has 4 divisors (see below), whose sum is σ = 160175472. Its totient is φ = 158769972.

The previous prime is 159472717. The next prime is 159472723. The reversal of 159472721 is 127274951.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 159472721 - 2² = 159472717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (159472723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 351035 + ... + 351488.

It is an arithmetic number, because the mean of its divisors is an integer number (40043868).

Almost surely, 2^159472721 is an apocalyptic number.

It is an amenable number.

159472721 is a deficient number, since it is larger than the sum of its proper divisors (702751).

159472721 is an equidigital number, since it uses as much as digits as its factorization.

159472721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 702750.

The product of its digits is 35280, while the sum is 38.

The square root of 159472721 is about 12628.2509081820. The cubic root of 159472721 is about 542.2865106013.

The spelling of 159472721 in words is "one hundred fifty-nine million, four hundred seventy-two thousand, seven hundred twenty-one".