78317306321 has 2 divisors, whose sum is σ = 78317306322. Its totient is φ = 78317306320.

The previous prime is 78317306293. The next prime is 78317306357. The reversal of 78317306321 is 12360371387.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64607472400 + 13709833921 = 254180^2 + 117089^2 .

It is a cyclic number.

It is not a de Polignac number, because 78317306321 - 2¹⁸ = 78317044177 is a prime.

It is a super-2 number, since 2×78317306321² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78317306381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39158653160 + 39158653161.

It is an arithmetic number, because the mean of its divisors is an integer number (39158653161).

Almost surely, 2^78317306321 is an apocalyptic number.

It is an amenable number.

78317306321 is a deficient number, since it is larger than the sum of its proper divisors (1).

78317306321 is an equidigital number, since it uses as much as digits as its factorization.

78317306321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 127008, while the sum is 41.

The spelling of 78317306321 in words is "seventy-eight billion, three hundred seventeen million, three hundred six thousand, three hundred twenty-one".