65640992489 has 2 divisors, whose sum is σ = 65640992490. Its totient is φ = 65640992488.

The previous prime is 65640992447. The next prime is 65640992533. The reversal of 65640992489 is 98429904656.

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., 61359253264 + 4281739225 = 247708^2 + 65435^2 .

It is a cyclic number.

It is not a de Polignac number, because 65640992489 - 2⁸ = 65640992233 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (65640992429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32820496244 + 32820496245.

It is an arithmetic number, because the mean of its divisors is an integer number (32820496245).

Almost surely, 2^65640992489 is an apocalyptic number.

It is an amenable number.

65640992489 is a deficient number, since it is larger than the sum of its proper divisors (1).

65640992489 is an equidigital number, since it uses as much as digits as its factorization.

65640992489 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 33592320, while the sum is 62.

The spelling of 65640992489 in words is "sixty-five billion, six hundred forty million, nine hundred ninety-two thousand, four hundred eighty-nine".