43721828130661 has 4 divisors (see below), whose sum is σ = 43721843210892. Its totient is φ = 43721813050432.

The previous prime is 43721828130649. The next prime is 43721828130671. The reversal of 43721828130661 is 16603182812734.

43721828130661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6364489566436 + 37357338564225 = 2522794^2 + 6112065^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43721828130661 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43721828130599 and 43721828130608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43721828130671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1665556 + ... + 9498301.

It is an arithmetic number, because the mean of its divisors is an integer number (10930460802723).

Almost surely, 2^{43721828130661} is an apocalyptic number.

It is an amenable number.

43721828130661 is a deficient number, since it is larger than the sum of its proper divisors (15080231).

43721828130661 is a wasteful number, since it uses less digits than its factorization.

43721828130661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15080230.

The product of its (nonzero) digits is 2322432, while the sum is 52.

The spelling of 43721828130661 in words is "forty-three trillion, seven hundred twenty-one billion, eight hundred twenty-eight million, one hundred thirty thousand, six hundred sixty-one".