978774451217 has 2 divisors, whose sum is σ = 978774451218. Its totient is φ = 978774451216.

The previous prime is 978774451199. The next prime is 978774451241. The reversal of 978774451217 is 712154477879.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 973016525056 + 5757926161 = 986416^2 + 75881^2 .

It is a cyclic number.

It is not a de Polignac number, because 978774451217 - 2⁶ = 978774451153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 978774451217.

It is not a weakly prime, because it can be changed into another prime (978774451247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 489387225608 + 489387225609.

It is an arithmetic number, because the mean of its divisors is an integer number (489387225609).

Almost surely, 2^978774451217 is an apocalyptic number.

It is an amenable number.

978774451217 is a deficient number, since it is larger than the sum of its proper divisors (1).

978774451217 is an equidigital number, since it uses as much as digits as its factorization.

978774451217 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27659520, while the sum is 62.

The spelling of 978774451217 in words is "nine hundred seventy-eight billion, seven hundred seventy-four million, four hundred fifty-one thousand, two hundred seventeen".