778888899999997 has 2 divisors, whose sum is σ = 778888899999998. Its totient is φ = 778888899999996.

The previous prime is 778888899999979. The next prime is 778888900000091. The reversal of 778888899999997 is 799999998888877.

Together with previous prime (778888899999979) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 707947934358681 + 70940965641316 = 26607291^2 + 8422646^2 .

It is a cyclic number.

It is not a de Polignac number, because 778888899999997 - 2³¹ = 778886752516349 is a prime.

It is a super-3 number, since 3×778888899999997³ (a number of 46 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (778888899999967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 389444449999998 + 389444449999999.

It is an arithmetic number, because the mean of its divisors is an integer number (389444449999999).

Almost surely, 2^{778888899999997} is an apocalyptic number.

It is an amenable number.

778888899999997 is a deficient number, since it is larger than the sum of its proper divisors (1).

778888899999997 is an equidigital number, since it uses as much as digits as its factorization.

778888899999997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53757816569856, while the sum is 124.

The spelling of 778888899999997 in words is "seven hundred seventy-eight trillion, eight hundred eighty-eight billion, eight hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-seven".