8561442961 has 4 divisors (see below), whose sum is σ = 8569027300. Its totient is φ = 8553858624.

The previous prime is 8561442937. The next prime is 8561442979. The reversal of 8561442961 is 1692441658.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1692441658 = 2 ⋅846220829.

It can be written as a sum of positive squares in 2 ways, for example, as 1850720400 + 6710722561 = 43020^2 + 81919^2 .

It is a cyclic number.

It is not a de Polignac number, because 8561442961 - 2⁷ = 8561442833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8561442931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3790476 + ... + 3792733.

It is an arithmetic number, because the mean of its divisors is an integer number (2142256825).

Almost surely, 2^8561442961 is an apocalyptic number.

It is an amenable number.

8561442961 is a deficient number, since it is larger than the sum of its proper divisors (7584339).

8561442961 is a wasteful number, since it uses less digits than its factorization.

8561442961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7584338.

The product of its digits is 414720, while the sum is 46.

The square root of 8561442961 is about 92528.0658016799. The cubic root of 8561442961 is about 2045.7331805138.

The spelling of 8561442961 in words is "eight billion, five hundred sixty-one million, four hundred forty-two thousand, nine hundred sixty-one".