6917218561 has 32 divisors (see below), whose sum is σ = 7942717440. Its totient is φ = 5967230400.

The previous prime is 6917218549. The next prime is 6917218577. The reversal of 6917218561 is 1658127196.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6917218561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6917218501) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8244180 + ... + 8245018.

It is an arithmetic number, because the mean of its divisors is an integer number (248209920).

Almost surely, 2^6917218561 is an apocalyptic number.

It is an amenable number.

6917218561 is a deficient number, since it is larger than the sum of its proper divisors (1025498879).

6917218561 is a wasteful number, since it uses less digits than its factorization.

6917218561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1365.

The product of its digits is 181440, while the sum is 46.

The square root of 6917218561 is about 83169.8176083127. The cubic root of 6917218561 is about 1905.3605369742.

The spelling of 6917218561 in words is "six billion, nine hundred seventeen million, two hundred eighteen thousand, five hundred sixty-one".