65921917 has 2 divisors, whose sum is σ = 65921918. Its totient is φ = 65921916.

The previous prime is 65921899. The next prime is 65921929. The reversal of 65921917 is 71912956.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57592921 + 8328996 = 7589^2 + 2886^2 .

It is a cyclic number.

It is not a de Polignac number, because 65921917 - 2⁷ = 65921789 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 65921917.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65921987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32960958 + 32960959.

It is an arithmetic number, because the mean of its divisors is an integer number (32960959).

Almost surely, 2^65921917 is an apocalyptic number.

It is an amenable number.

65921917 is a deficient number, since it is larger than the sum of its proper divisors (1).

65921917 is an equidigital number, since it uses as much as digits as its factorization.

65921917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34020, while the sum is 40.

The square root of 65921917 is about 8119.2313059796. The cubic root of 65921917 is about 403.9645694021.

The spelling of 65921917 in words is "sixty-five million, nine hundred twenty-one thousand, nine hundred seventeen".