65908781 has 2 divisors, whose sum is σ = 65908782. Its totient is φ = 65908780.

The previous prime is 65908763. The next prime is 65908783. The reversal of 65908781 is 18780956.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 60918025 + 4990756 = 7805^2 + 2234^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-65908781 is a prime.

It is a super-2 number, since 2×65908781² = 8687934825811922, which contains 22 as substring.

Together with 65908783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65908783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32954390 + 32954391.

It is an arithmetic number, because the mean of its divisors is an integer number (32954391).

Almost surely, 2^65908781 is an apocalyptic number.

It is an amenable number.

65908781 is a deficient number, since it is larger than the sum of its proper divisors (1).

65908781 is an equidigital number, since it uses as much as digits as its factorization.

65908781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120960, while the sum is 44.

The square root of 65908781 is about 8118.4223221018. The cubic root of 65908781 is about 403.9377354783.

The spelling of 65908781 in words is "sixty-five million, nine hundred eight thousand, seven hundred eighty-one".