9990056561 has 8 divisors (see below), whose sum is σ = 10343327400. Its totient is φ = 9637371520.

The previous prime is 9990056533. The next prime is 9990056563. The reversal of 9990056561 is 1656500999.

9990056561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 2235492961 + 7754563600 = 47281^2 + 88060^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9990056561 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (9990056563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111596 + ... + 180093.

It is an arithmetic number, because the mean of its divisors is an integer number (1292915925).

Almost surely, 2^9990056561 is an apocalyptic number.

It is an amenable number.

9990056561 is a deficient number, since it is larger than the sum of its proper divisors (353270839).

9990056561 is a wasteful number, since it uses less digits than its factorization.

9990056561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 292899.

The product of its (nonzero) digits is 656100, while the sum is 50.

The square root of 9990056561 is about 99950.2704398542. The cubic root of 9990056561 is about 2153.7203702224.

The spelling of 9990056561 in words is "nine billion, nine hundred ninety million, fifty-six thousand, five hundred sixty-one".