66533309 has 2 divisors, whose sum is σ = 66533310. Its totient is φ = 66533308.

The previous prime is 66533287. The next prime is 66533321. The reversal of 66533309 is 90333566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47914084 + 18619225 = 6922^2 + 4315^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66533309 is a prime.

It is a super-3 number, since 3×66533309³ (a number of 24 digits) contains 333 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66533329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33266654 + 33266655.

It is an arithmetic number, because the mean of its divisors is an integer number (33266655).

Almost surely, 2^66533309 is an apocalyptic number.

It is an amenable number.

66533309 is a deficient number, since it is larger than the sum of its proper divisors (1).

66533309 is an equidigital number, since it uses as much as digits as its factorization.

66533309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43740, while the sum is 35.

The square root of 66533309 is about 8156.7952652987. The cubic root of 66533309 is about 405.2095831363.

The spelling of 66533309 in words is "sixty-six million, five hundred thirty-three thousand, three hundred nine".