66488689 has 2 divisors, whose sum is σ = 66488690. Its totient is φ = 66488688.

The previous prime is 66488687. The next prime is 66488701. The reversal of 66488689 is 98688466.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53290000 + 13198689 = 7300^2 + 3633^2 .

It is a cyclic number.

It is not a de Polignac number, because 66488689 - 2¹ = 66488687 is a prime.

Together with 66488687, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66488687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33244344 + 33244345.

It is an arithmetic number, because the mean of its divisors is an integer number (33244345).

Almost surely, 2^66488689 is an apocalyptic number.

It is an amenable number.

66488689 is a deficient number, since it is larger than the sum of its proper divisors (1).

66488689 is an equidigital number, since it uses as much as digits as its factorization.

66488689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3981312, while the sum is 55.

The square root of 66488689 is about 8154.0596637503. The cubic root of 66488689 is about 405.1189794211.

The spelling of 66488689 in words is "sixty-six million, four hundred eighty-eight thousand, six hundred eighty-nine".