78217560368641 has 8 divisors (see below), whose sum is σ = 78587228201768. Its totient is φ = 77848265376000.

The previous prime is 78217560368617. The next prime is 78217560368663. The reversal of 78217560368641 is 14686306571287.

It can be written as a sum of positive squares in 4 ways, for example, as 10632653600625 + 67584906768016 = 3260775^2 + 8221004^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78217560368641 - 2¹⁷ = 78217560237569 is a prime.

It is a super-2 number, since 2×78217560368641² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78217560318641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 92789550 + ... + 93628711.

It is an arithmetic number, because the mean of its divisors is an integer number (9823403525221).

Almost surely, 2^{78217560368641} is an apocalyptic number.

It is an amenable number.

78217560368641 is a deficient number, since it is larger than the sum of its proper divisors (369667833127).

78217560368641 is a wasteful number, since it uses less digits than its factorization.

78217560368641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186420243.

The product of its (nonzero) digits is 81285120, while the sum is 64.

The spelling of 78217560368641 in words is "seventy-eight trillion, two hundred seventeen billion, five hundred sixty million, three hundred sixty-eight thousand, six hundred forty-one".