8720681553 has 24 divisors (see below), whose sum is σ = 13037305320. Its totient is φ = 5610554880.

The previous prime is 8720681531. The next prime is 8720681597. The reversal of 8720681553 is 3551860278.

It can be written as a sum of positive squares in 4 ways, for example, as 317659329 + 8403022224 = 17823^2 + 91668^2 .

It is not a de Polignac number, because 8720681553 - 2⁸ = 8720681297 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 8720681499 and 8720681508.

It is not an unprimeable number, because it can be changed into a prime (8720681513) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 614425 + ... + 628457.

It is an arithmetic number, because the mean of its divisors is an integer number (543221055).

Almost surely, 2^8720681553 is an apocalyptic number.

It is an amenable number.

8720681553 is a deficient number, since it is larger than the sum of its proper divisors (4316623767).

8720681553 is a wasteful number, since it uses less digits than its factorization.

8720681553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16449 (or 16446 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 45.

The square root of 8720681553 is about 93384.5894834903. The cubic root of 8720681553 is about 2058.3385567563.

The spelling of 8720681553 in words is "eight billion, seven hundred twenty million, six hundred eighty-one thousand, five hundred fifty-three".