99433639561 has 9 divisors (see below), whose sum is σ = 101931255079. Its totient is φ = 96995815600.

The previous prime is 99433639553. The next prime is 99433639579. The reversal of 99433639561 is 16593633499.

The square root of 99433639561 is 315331.

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., 4791269961 + 94642369600 = 69219^2 + 307640^2 .

It is not a de Polignac number, because 99433639561 - 2³ = 99433639553 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 99433639496 and 99433639505.

It is not an unprimeable number, because it can be changed into a prime (99433639511) 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, 12924726 + ... + 12932416.

Almost surely, 2^99433639561 is an apocalyptic number.

99433639561 is the 315331-st square number.

99433639561 is the 157666-th centered octagonal number.

It is an amenable number.

99433639561 is a deficient number, since it is larger than the sum of its proper divisors (2497615518).

99433639561 is an frugal number, since it uses more digits than its factorization.

99433639561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15464 (or 7732 counting only the distinct ones).

The product of its digits is 14171760, while the sum is 58.

The spelling of 99433639561 in words is "ninety-nine billion, four hundred thirty-three million, six hundred thirty-nine thousand, five hundred sixty-one".