65821979 has 2 divisors, whose sum is σ = 65821980. Its totient is φ = 65821978.

The previous prime is 65821963. The next prime is 65822017. The reversal of 65821979 is 97912856.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 65821979 - 2⁴ = 65821963 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (65821079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32910989 + 32910990.

It is an arithmetic number, because the mean of its divisors is an integer number (32910990).

Almost surely, 2^65821979 is an apocalyptic number.

65821979 is a deficient number, since it is larger than the sum of its proper divisors (1).

65821979 is an equidigital number, since it uses as much as digits as its factorization.

65821979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 272160, while the sum is 47.

The square root of 65821979 is about 8113.0745713324. The cubic root of 65821979 is about 403.7603286312.

The spelling of 65821979 in words is "sixty-five million, eight hundred twenty-one thousand, nine hundred seventy-nine".