66242389 has 2 divisors, whose sum is σ = 66242390. Its totient is φ = 66242388.

The previous prime is 66242359. The next prime is 66242437. The reversal of 66242389 is 98324266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64931364 + 1311025 = 8058^2 + 1145^2 .

It is a cyclic number.

It is not a de Polignac number, because 66242389 - 2⁵ = 66242357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66242329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33121194 + 33121195.

It is an arithmetic number, because the mean of its divisors is an integer number (33121195).

Almost surely, 2^66242389 is an apocalyptic number.

It is an amenable number.

66242389 is a deficient number, since it is larger than the sum of its proper divisors (1).

66242389 is an equidigital number, since it uses as much as digits as its factorization.

66242389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 124416, while the sum is 40.

The square root of 66242389 is about 8138.9427446076. The cubic root of 66242389 is about 404.6181209578.

The spelling of 66242389 in words is "sixty-six million, two hundred forty-two thousand, three hundred eighty-nine".