720546649 has 9 divisors (see below), whose sum is σ = 765910047. Its totient is φ = 677732064.

The previous prime is 720546641. The next prime is 720546653. The reversal of 720546649 is 946645027.

It is a happy number.

The square root of 720546649 is 26843.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 560979225 + 159567424 = 23685^2 + 12632^2 .

It is not a de Polignac number, because 720546649 - 2³ = 720546641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (720546641) 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 8 ways as a sum of consecutive naturals, for example, 455542 + ... + 457120.

Almost surely, 2^720546649 is an apocalyptic number.

720546649 is the 26843-rd square number.

720546649 is the 13422-nd centered octagonal number.

It is an amenable number.

720546649 is a deficient number, since it is larger than the sum of its proper divisors (45363398).

720546649 is an frugal number, since it uses more digits than its factorization.

720546649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3192 (or 1596 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 43.

The cubic root of 720546649 is about 896.5077211360.

The spelling of 720546649 in words is "seven hundred twenty million, five hundred forty-six thousand, six hundred forty-nine".