13556643489 has 45 divisors (see below), whose sum is σ = 21540913801. Its totient is φ = 8494951680.

The previous prime is 13556643487. The next prime is 13556643547. The reversal of 13556643489 is 98434665531.

The square root of 13556643489 is 116433.

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

13556643489 is a `hidden beast` number, since 1 + 3 + 556 + 6 + 4 + 3 + 4 + 89 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2445797025 + 11110846464 = 49455^2 + 105408^2 .

It is not a de Polignac number, because 13556643489 - 2¹ = 13556643487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13556643487) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 17813869 + ... + 17814629.

Almost surely, 2^13556643489 is an apocalyptic number.

13556643489 is the 116433-rd square number.

13556643489 is the 58217-th centered octagonal number.

It is an amenable number.

13556643489 is a deficient number, since it is larger than the sum of its proper divisors (7984270312).

13556643489 is an frugal number, since it uses more digits than its factorization.

13556643489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1568 (or 781 counting only the distinct ones).

The product of its digits is 9331200, while the sum is 54.

The spelling of 13556643489 in words is "thirteen billion, five hundred fifty-six million, six hundred forty-three thousand, four hundred eighty-nine".