10809556508521 has 9 divisors (see below), whose sum is σ = 10911879673149. Its totient is φ = 10708184110284.

The previous prime is 10809556508507. The next prime is 10809556508539. The reversal of 10809556508521 is 12580565590801.

The square root of 10809556508521 is 3287789.

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

It is not a de Polignac number, because 10809556508521 - 2¹¹ = 10809556506473 is a prime.

It is a super-3 number, since 3×10809556508521³ (a number of 40 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (10809556508551) 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, 351778060 + ... + 351808786.

Almost surely, 2^{10809556508521} is an apocalyptic number.

10809556508521 is the 3287789-th square number.

10809556508521 is the 1643895-th centered octagonal number.

It is an amenable number.

10809556508521 is a deficient number, since it is larger than the sum of its proper divisors (102323164628).

10809556508521 is an frugal number, since it uses more digits than its factorization.

10809556508521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61668 (or 30834 counting only the distinct ones).

The product of its (nonzero) digits is 4320000, while the sum is 55.

The spelling of 10809556508521 in words is "ten trillion, eight hundred nine billion, five hundred fifty-six million, five hundred eight thousand, five hundred twenty-one".