4123685561 has 4 divisors (see below), whose sum is σ = 4123854324. Its totient is φ = 4123516800.

The previous prime is 4123685551. The next prime is 4123685591. The reversal of 4123685561 is 1655863214.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1655863214 = 2 ⋅827931607.

It can be written as a sum of positive squares in 2 ways, for example, as 2916540025 + 1207145536 = 54005^2 + 34744^2 .

It is a cyclic number.

It is not a de Polignac number, because 4123685561 - 2³⁰ = 3049943737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4123685521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39920 + ... + 99201.

It is an arithmetic number, because the mean of its divisors is an integer number (1030963581).

Almost surely, 2^4123685561 is an apocalyptic number.

It is an amenable number.

4123685561 is a deficient number, since it is larger than the sum of its proper divisors (168763).

4123685561 is a wasteful number, since it uses less digits than its factorization.

4123685561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168762.

The product of its digits is 172800, while the sum is 41.

The square root of 4123685561 is about 64215.9291842764. The cubic root of 4123685561 is about 1603.5967990941.

The spelling of 4123685561 in words is "four billion, one hundred twenty-three million, six hundred eighty-five thousand, five hundred sixty-one".