99609040881 has 135 divisors (see below), whose sum is σ = 178730406699. Its totient is φ = 53446490496.

The previous prime is 99609040879. The next prime is 99609040943. The reversal of 99609040881 is 18804090699.

The square root of 99609040881 is 315609.

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

99609040881 is a `hidden beast` number, since 99 + 60 + 90 + 408 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1755191025 + 97853849856 = 41895^2 + 312816^2 .

It is not a de Polignac number, because 99609040881 - 2¹ = 99609040879 is a prime.

It is a super-2 number, since 2×99609040881² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (99609040801) by changing a digit.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 881495881 + ... + 881495993.

Almost surely, 2^99609040881 is an apocalyptic number.

99609040881 is the 315609-th square number.

99609040881 is the 157805-th centered octagonal number.

It is an amenable number.

99609040881 is a deficient number, since it is larger than the sum of its proper divisors (79121365818).

99609040881 is an equidigital number, since it uses as much as digits as its factorization.

99609040881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 54.

The spelling of 99609040881 in words is "ninety-nine billion, six hundred nine million, forty thousand, eight hundred eighty-one".