41561231661 has 12 divisors (see below), whose sum is σ = 63564236892. Its totient is φ = 26077635456.

The previous prime is 41561231629. The next prime is 41561231681. The reversal of 41561231661 is 16613216514.

41561231661 is a `hidden beast` number, since 4 + 1 + 5 + 612 + 31 + 6 + 6 + 1 = 666.

41561231661 is digitally balanced in base 2, 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 2 ways, for example, as 30802356036 + 10758875625 = 175506^2 + 103725^2 .

It is not a de Polignac number, because 41561231661 - 2⁵ = 41561231629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (41561231681) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 135820866 + ... + 135821171.

It is an arithmetic number, because the mean of its divisors is an integer number (5297019741).

Almost surely, 2^41561231661 is an apocalyptic number.

It is an amenable number.

41561231661 is a deficient number, since it is larger than the sum of its proper divisors (22003005231).

41561231661 is a wasteful number, since it uses less digits than its factorization.

41561231661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271642060 (or 271642057 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The spelling of 41561231661 in words is "forty-one billion, five hundred sixty-one million, two hundred thirty-one thousand, six hundred sixty-one".