6720556441 has 9 divisors (see below), whose sum is σ = 6819952959. Its totient is φ = 6622591536.

The previous prime is 6720556393. The next prime is 6720556489. The reversal of 6720556441 is 1446550276.

It is a happy number.

The square root of 6720556441 is 81979.

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

It is an interprime number because it is at equal distance from previous prime (6720556393) and next prime (6720556489).

It can be written as a sum of positive squares in only one way, i.e., 3814915225 + 2905641216 = 61765^2 + 53904^2 .

It is not a de Polignac number, because 6720556441 - 2⁷ = 6720556313 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6720556394 and 6720556403.

It is not an unprimeable number, because it can be changed into a prime (6720556741) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5983906 + ... + 5985028.

It is an arithmetic number, because the mean of its divisors is an integer number (757772551).

Almost surely, 2^6720556441 is an apocalyptic number.

6720556441 is the 81979-th square number.

6720556441 is the 40990-th centered octagonal number.

It is an amenable number.

6720556441 is a deficient number, since it is larger than the sum of its proper divisors (99396518).

6720556441 is an frugal number, since it uses more digits than its factorization.

6720556441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2392 (or 1196 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 40.

The cubic root of 6720556441 is about 1887.1296763707.

The spelling of 6720556441 in words is "six billion, seven hundred twenty million, five hundred fifty-six thousand, four hundred forty-one".