65660981 has 2 divisors, whose sum is σ = 65660982. Its totient is φ = 65660980.

The previous prime is 65660963. The next prime is 65661047. The reversal of 65660981 is 18906656.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65060356 + 600625 = 8066^2 + 775^2 .

It is a cyclic number.

It is not a de Polignac number, because 65660981 - 2²² = 61466677 is a prime.

It is a super-2 number, since 2×65660981² = 8622728851764722, which contains 22 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 (65660921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32830490 + 32830491.

It is an arithmetic number, because the mean of its divisors is an integer number (32830491).

Almost surely, 2^65660981 is an apocalyptic number.

It is an amenable number.

65660981 is a deficient number, since it is larger than the sum of its proper divisors (1).

65660981 is an equidigital number, since it uses as much as digits as its factorization.

65660981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 41.

The square root of 65660981 is about 8103.1463642217. The cubic root of 65660981 is about 403.4308658485.

The spelling of 65660981 in words is "sixty-five million, six hundred sixty thousand, nine hundred eighty-one".