721159985 has 16 divisors (see below), whose sum is σ = 1065098496. Its totient is φ = 456470208.

The previous prime is 721159973. The next prime is 721159987. The reversal of 721159985 is 589951127.

It is a happy number.

721159985 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 721159985 - 2⁶ = 721159921 is a prime.

It is not an unprimeable number, because it can be changed into a prime (721159987) 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, 792029 + ... + 792938.

It is an arithmetic number, because the mean of its divisors is an integer number (66568656).

Almost surely, 2^721159985 is an apocalyptic number.

It is an amenable number.

721159985 is a deficient number, since it is larger than the sum of its proper divisors (343938511).

721159985 is a wasteful number, since it uses less digits than its factorization.

721159985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1584992.

The product of its digits is 226800, while the sum is 47.

The square root of 721159985 is about 26854.4220753305. The cubic root of 721159985 is about 896.7620208951.

The spelling of 721159985 in words is "seven hundred twenty-one million, one hundred fifty-nine thousand, nine hundred eighty-five".