866828644377677 has 2 divisors, whose sum is σ = 866828644377678. Its totient is φ = 866828644377676.

The previous prime is 866828644377673. The next prime is 866828644377743. The reversal of 866828644377677 is 776773446828668.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 866716602882601 + 112041495076 = 29440051^2 + 334726^2 .

It is a cyclic number.

It is not a de Polignac number, because 866828644377677 - 2² = 866828644377673 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 866828644377592 and 866828644377601.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866828644377673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433414322188838 + 433414322188839.

It is an arithmetic number, because the mean of its divisors is an integer number (433414322188839).

Almost surely, 2^{866828644377677} is an apocalyptic number.

It is an amenable number.

866828644377677 is a deficient number, since it is larger than the sum of its proper divisors (1).

866828644377677 is an equidigital number, since it uses as much as digits as its factorization.

866828644377677 is an evil number, because the sum of its binary digits is even.

The product of its digits is 152946081792, while the sum is 89.

The spelling of 866828644377677 in words is "eight hundred sixty-six trillion, eight hundred twenty-eight billion, six hundred forty-four million, three hundred seventy-seven thousand, six hundred seventy-seven".