6646778118567 has 24 divisors (see below), whose sum is σ = 10700695427760. Its totient is φ = 3951026000640.

The previous prime is 6646778118523. The next prime is 6646778118619. The reversal of 6646778118567 is 7658118776466.

6646778118567 is a `hidden beast` number, since 6 + 6 + 46 + 7 + 7 + 8 + 1 + 18 + 567 = 666.

It is not a de Polignac number, because 6646778118567 - 2¹¹ = 6646778116519 is a prime.

It is a super-2 number, since 2×6646778118567² (a number of 26 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 6646778118495 and 6646778118504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6646778118367) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1143233784 + ... + 1143239597.

It is an arithmetic number, because the mean of its divisors is an integer number (445862309490).

Almost surely, 2^{6646778118567} is an apocalyptic number.

6646778118567 is a deficient number, since it is larger than the sum of its proper divisors (4053917309193).

6646778118567 is a wasteful number, since it uses less digits than its factorization.

6646778118567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2286473423 (or 2286473420 counting only the distinct ones).

The product of its digits is 568995840, while the sum is 72.

The spelling of 6646778118567 in words is "six trillion, six hundred forty-six billion, seven hundred seventy-eight million, one hundred eighteen thousand, five hundred sixty-seven".