78882217657 has 2 divisors, whose sum is σ = 78882217658. Its totient is φ = 78882217656.

The previous prime is 78882217621. The next prime is 78882217663. The reversal of 78882217657 is 75671228887.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46175133456 + 32707084201 = 214884^2 + 180851^2 .

It is a cyclic number.

It is not a de Polignac number, because 78882217657 - 2¹¹ = 78882215609 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78882217595 and 78882217604.

It is not a weakly prime, because it can be changed into another prime (78882217457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39441108828 + 39441108829.

It is an arithmetic number, because the mean of its divisors is an integer number (39441108829).

Almost surely, 2^78882217657 is an apocalyptic number.

It is an amenable number.

78882217657 is a deficient number, since it is larger than the sum of its proper divisors (1).

78882217657 is an equidigital number, since it uses as much as digits as its factorization.

78882217657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21073920, while the sum is 61.

The spelling of 78882217657 in words is "seventy-eight billion, eight hundred eighty-two million, two hundred seventeen thousand, six hundred fifty-seven".