66309983 has 2 divisors, whose sum is σ = 66309984. Its totient is φ = 66309982.

The previous prime is 66309977. The next prime is 66310001. The reversal of 66309983 is 38990366.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66309983 - 2¹⁶ = 66244447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66309583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33154991 + 33154992.

It is an arithmetic number, because the mean of its divisors is an integer number (33154992).

Almost surely, 2^66309983 is an apocalyptic number.

66309983 is a deficient number, since it is larger than the sum of its proper divisors (1).

66309983 is an equidigital number, since it uses as much as digits as its factorization.

66309983 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 209952, while the sum is 44.

The square root of 66309983 is about 8143.0941907852. The cubic root of 66309983 is about 404.7556988257.

The spelling of 66309983 in words is "sixty-six million, three hundred nine thousand, nine hundred eighty-three".