66421589837 has 2 divisors, whose sum is σ = 66421589838. Its totient is φ = 66421589836.

The previous prime is 66421589827. The next prime is 66421589863. The reversal of 66421589837 is 73898512466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 63513576361 + 2908013476 = 252019^2 + 53926^2 .

It is a cyclic number.

It is not a de Polignac number, because 66421589837 - 2⁸ = 66421589581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66421589827) 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, 33210794918 + 33210794919.

It is an arithmetic number, because the mean of its divisors is an integer number (33210794919).

Almost surely, 2^66421589837 is an apocalyptic number.

It is an amenable number.

66421589837 is a deficient number, since it is larger than the sum of its proper divisors (1).

66421589837 is an equidigital number, since it uses as much as digits as its factorization.

66421589837 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17418240, while the sum is 59.

The spelling of 66421589837 in words is "sixty-six billion, four hundred twenty-one million, five hundred eighty-nine thousand, eight hundred thirty-seven".