9447768661 has 4 divisors (see below), whose sum is σ = 9752535424. Its totient is φ = 9143001900.

The previous prime is 9447768641. The next prime is 9447768739. The reversal of 9447768661 is 1668677449.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 9447768661 - 2²¹ = 9445671509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 9447768596 and 9447768605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9447768641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 152383335 + ... + 152383396.

It is an arithmetic number, because the mean of its divisors is an integer number (2438133856).

Almost surely, 2^9447768661 is an apocalyptic number.

It is an amenable number.

9447768661 is a deficient number, since it is larger than the sum of its proper divisors (304766763).

9447768661 is a wasteful number, since it uses less digits than its factorization.

9447768661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304766762.

The product of its digits is 12192768, while the sum is 58.

The square root of 9447768661 is about 97199.6330291427. The cubic root of 9447768661 is about 2114.0232053303.

The spelling of 9447768661 in words is "nine billion, four hundred forty-seven million, seven hundred sixty-eight thousand, six hundred sixty-one".