66000421 has 2 divisors, whose sum is σ = 66000422. Its totient is φ = 66000420.

The previous prime is 66000419. The next prime is 66000469. The reversal of 66000421 is 12400066.

66000421 is nontrivially palindromic in base 6.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33350625 + 32649796 = 5775^2 + 5714^2 .

It is a cyclic number.

It is not a de Polignac number, because 66000421 - 2¹ = 66000419 is a prime.

Together with 66000419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66000821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33000210 + 33000211.

It is an arithmetic number, because the mean of its divisors is an integer number (33000211).

Almost surely, 2^66000421 is an apocalyptic number.

It is an amenable number.

66000421 is a deficient number, since it is larger than the sum of its proper divisors (1).

66000421 is an equidigital number, since it uses as much as digits as its factorization.

66000421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 66000421 is about 8124.0643153535. The cubic root of 66000421 is about 404.1248613342.

Adding to 66000421 its reverse (12400066), we get a palindrome (78400487).

The spelling of 66000421 in words is "sixty-six million, four hundred twenty-one", and thus it is an aban number.