9918613280689 has 27 divisors (see below), whose sum is σ = 10818718533081. Its totient is φ = 9091764819720.

The previous prime is 9918613280621. The next prime is 9918613280701. The reversal of 9918613280689 is 9860823168199.

The square root of 9918613280689 is 3149383.

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

It is a de Polignac number, because none of the positive numbers 2^k-9918613280689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9918613230689) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1854983914 + ... + 1854989260.

It is an arithmetic number, because the mean of its divisors is an integer number (400693279003).

Almost surely, 2^{9918613280689} is an apocalyptic number.

9918613280689 is the 3149383-rd square number.

9918613280689 is the 1574692-nd centered octagonal number.

It is an amenable number.

9918613280689 is a deficient number, since it is larger than the sum of its proper divisors (900105252392).

9918613280689 is an frugal number, since it uses more digits than its factorization.

9918613280689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10794 (or 5397 counting only the distinct ones).

The product of its (nonzero) digits is 80621568, while the sum is 70.

The spelling of 9918613280689 in words is "nine trillion, nine hundred eighteen billion, six hundred thirteen million, two hundred eighty thousand, six hundred eighty-nine".