99660109306081 has 9 divisors (see below), whose sum is σ = 100876138769811. Its totient is φ = 98458566492312.

The previous prime is 99660109306039. The next prime is 99660109306139. The reversal of 99660109306081 is 18060390106699.

The square root of 99660109306081 is 9982991.

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

It can be written as a sum of positive squares in only one way, i.e., 8635458118225 + 91024651187856 = 2938615^2 + 9540684^2 .

It is not a de Polignac number, because 99660109306081 - 2²³ = 99660100917473 is a prime.

It is a super-2 number, since 2×99660109306081² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99660109306781) 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, 828528115 + ... + 828648391.

Almost surely, 2^{99660109306081} is an apocalyptic number.

99660109306081 is the 9982991-st square number.

99660109306081 is the 4991496-th centered octagonal number.

It is an amenable number.

99660109306081 is a deficient number, since it is larger than the sum of its proper divisors (1216029463730).

99660109306081 is an frugal number, since it uses more digits than its factorization.

99660109306081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240720 (or 120360 counting only the distinct ones).

The product of its (nonzero) digits is 3779136, while the sum is 58.

The spelling of 99660109306081 in words is "ninety-nine trillion, six hundred sixty billion, one hundred nine million, three hundred six thousand, eighty-one".