866764402430557 has 2 divisors, whose sum is σ = 866764402430558. Its totient is φ = 866764402430556.

The previous prime is 866764402430527. The next prime is 866764402430699. The reversal of 866764402430557 is 755034204467668.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 709156314140121 + 157608088290436 = 26629989^2 + 12554206^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-866764402430557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 866764402430492 and 866764402430501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866764402430527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433382201215278 + 433382201215279.

It is an arithmetic number, because the mean of its divisors is an integer number (433382201215279).

Almost surely, 2^{866764402430557} is an apocalyptic number.

It is an amenable number.

866764402430557 is a deficient number, since it is larger than the sum of its proper divisors (1).

866764402430557 is an equidigital number, since it uses as much as digits as its factorization.

866764402430557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 812851200, while the sum is 67.

The spelling of 866764402430557 in words is "eight hundred sixty-six trillion, seven hundred sixty-four billion, four hundred two million, four hundred thirty thousand, five hundred fifty-seven".