66361 has 2 divisors, whose sum is σ = 66362. Its totient is φ = 66360.

The previous prime is 66359. The next prime is 66373. The reversal of 66361 is 16366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 42025 + 24336 = 205^2 + 156^2 .

It is a cyclic number.

It is not a de Polignac number, because 66361 - 2¹ = 66359 is a prime.

Together with 66359, 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 (66301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33180 + 33181.

It is an arithmetic number, because the mean of its divisors is an integer number (33181).

2⁶⁶³⁶¹ is an apocalyptic number.

It is an amenable number.

66361 is a deficient number, since it is larger than the sum of its proper divisors (1).

66361 is an equidigital number, since it uses as much as digits as its factorization.

66361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 22.

The square root of 66361 is about 257.6062887431. The cubic root of 66361 is about 40.4859474693.

The spelling of 66361 in words is "sixty-six thousand, three hundred sixty-one".