65855986917 has 48 divisors (see below), whose sum is σ = 108853051392. Its totient is φ = 35229865440.

The previous prime is 65855986879. The next prime is 65855986951. The reversal of 65855986917 is 71968955856.

It is a happy number.

It is not a de Polignac number, because 65855986917 - 2⁸ = 65855986661 is a prime.

It is a super-2 number, since 2×65855986917² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (69).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65855986957) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 48309 + ... + 366122.

It is an arithmetic number, because the mean of its divisors is an integer number (2267771904).

Almost surely, 2^65855986917 is an apocalyptic number.

It is an amenable number.

65855986917 is a deficient number, since it is larger than the sum of its proper divisors (42997064475).

65855986917 is a wasteful number, since it uses less digits than its factorization.

65855986917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414518 (or 414511 counting only the distinct ones).

The product of its digits is 163296000, while the sum is 69.

The spelling of 65855986917 in words is "sixty-five billion, eight hundred fifty-five million, nine hundred eighty-six thousand, nine hundred seventeen".