41821609861 has 2 divisors, whose sum is σ = 41821609862. Its totient is φ = 41821609860.

The previous prime is 41821609831. The next prime is 41821609877. The reversal of 41821609861 is 16890612814.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38585137761 + 3236472100 = 196431^2 + 56890^2 .

It is a cyclic number.

It is not a de Polignac number, because 41821609861 - 2⁵ = 41821609829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (41821609801) 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 as a sum of consecutive naturals, namely, 20910804930 + 20910804931.

It is an arithmetic number, because the mean of its divisors is an integer number (20910804931).

Almost surely, 2^41821609861 is an apocalyptic number.

It is an amenable number.

41821609861 is a deficient number, since it is larger than the sum of its proper divisors (1).

41821609861 is an equidigital number, since it uses as much as digits as its factorization.

41821609861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 165888, while the sum is 46.

The spelling of 41821609861 in words is "forty-one billion, eight hundred twenty-one million, six hundred nine thousand, eight hundred sixty-one".