65855967217 has 4 divisors (see below), whose sum is σ = 66358684656. Its totient is φ = 65353249780.

The previous prime is 65855967197. The next prime is 65855967227. The reversal of 65855967217 is 71276955856.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 65855967217 - 2³⁵ = 31496228849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (65855967227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 251358523 + ... + 251358784.

It is an arithmetic number, because the mean of its divisors is an integer number (16589671164).

Almost surely, 2^65855967217 is an apocalyptic number.

It is an amenable number.

65855967217 is a deficient number, since it is larger than the sum of its proper divisors (502717439).

65855967217 is a wasteful number, since it uses less digits than its factorization.

65855967217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 502717438.

The product of its digits is 31752000, while the sum is 61.

The spelling of 65855967217 in words is "sixty-five billion, eight hundred fifty-five million, nine hundred sixty-seven thousand, two hundred seventeen".