41647641821 has 2 divisors, whose sum is σ = 41647641822. Its totient is φ = 41647641820.

The previous prime is 41647641799. The next prime is 41647641877. The reversal of 41647641821 is 12814674614.

41647641821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36869376196 + 4778265625 = 192014^2 + 69125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-41647641821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (41647641881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20823820910 + 20823820911.

It is an arithmetic number, because the mean of its divisors is an integer number (20823820911).

Almost surely, 2^41647641821 is an apocalyptic number.

It is an amenable number.

41647641821 is a deficient number, since it is larger than the sum of its proper divisors (1).

41647641821 is an equidigital number, since it uses as much as digits as its factorization.

41647641821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 258048, while the sum is 44.

The spelling of 41647641821 in words is "forty-one billion, six hundred forty-seven million, six hundred forty-one thousand, eight hundred twenty-one".