66561283 has 2 divisors, whose sum is σ = 66561284. Its totient is φ = 66561282.

The previous prime is 66561281. The next prime is 66561289. The reversal of 66561283 is 38216566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66561283 - 2¹ = 66561281 is a prime.

Together with 66561281, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66561281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33280641 + 33280642.

It is an arithmetic number, because the mean of its divisors is an integer number (33280642).

Almost surely, 2^66561283 is an apocalyptic number.

66561283 is a deficient number, since it is larger than the sum of its proper divisors (1).

66561283 is an equidigital number, since it uses as much as digits as its factorization.

66561283 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51840, while the sum is 37.

The square root of 66561283 is about 8158.5098516825. The cubic root of 66561283 is about 405.2663654447.

The spelling of 66561283 in words is "sixty-six million, five hundred sixty-one thousand, two hundred eighty-three".