721435065 has 32 divisors (see below), whose sum is σ = 1276697856. Its totient is φ = 345565440.

The previous prime is 721435063. The next prime is 721435081. The reversal of 721435065 is 560534127.

It is not a de Polignac number, because 721435065 - 2¹ = 721435063 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (721435061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42781 + ... + 57210.

It is an arithmetic number, because the mean of its divisors is an integer number (39896808).

Almost surely, 2^721435065 is an apocalyptic number.

It is an amenable number.

721435065 is a deficient number, since it is larger than the sum of its proper divisors (555262791).

721435065 is a wasteful number, since it uses less digits than its factorization.

721435065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100049.

The product of its (nonzero) digits is 25200, while the sum is 33.

The square root of 721435065 is about 26859.5432760872. The cubic root of 721435065 is about 896.8760270074.

The spelling of 721435065 in words is "seven hundred twenty-one million, four hundred thirty-five thousand, sixty-five".