720525665 has 8 divisors (see below), whose sum is σ = 865983528. Its totient is φ = 575518720.

The previous prime is 720525661. The next prime is 720525667. The reversal of 720525665 is 566525027.

720525665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 352538176 + 367987489 = 18776^2 + 19183^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 720525665 - 2² = 720525661 is a prime.

It is a super-3 number, since 3×720525665³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (720525661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 109202 + ... + 115611.

It is an arithmetic number, because the mean of its divisors is an integer number (108247941).

Almost surely, 2^720525665 is an apocalyptic number.

It is an amenable number.

720525665 is a deficient number, since it is larger than the sum of its proper divisors (145457863).

720525665 is a wasteful number, since it uses less digits than its factorization.

720525665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225459.

The product of its (nonzero) digits is 126000, while the sum is 38.

The square root of 720525665 is about 26842.6091317517. The cubic root of 720525665 is about 896.4990182525.

The spelling of 720525665 in words is "seven hundred twenty million, five hundred twenty-five thousand, six hundred sixty-five".