866760686880421 has 2 divisors, whose sum is σ = 866760686880422. Its totient is φ = 866760686880420.

The previous prime is 866760686880409. The next prime is 866760686880443. The reversal of 866760686880421 is 124088686067668.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 500153460820321 + 366607226060100 = 22364111^2 + 19146990^2 .

It is a cyclic number.

It is not a de Polignac number, because 866760686880421 - 2¹⁹ = 866760686356133 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866760686880461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433380343440210 + 433380343440211.

It is an arithmetic number, because the mean of its divisors is an integer number (433380343440211).

Almost surely, 2^{866760686880421} is an apocalyptic number.

It is an amenable number.

866760686880421 is a deficient number, since it is larger than the sum of its proper divisors (1).

866760686880421 is an equidigital number, since it uses as much as digits as its factorization.

866760686880421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1783627776, while the sum is 76.

The spelling of 866760686880421 in words is "eight hundred sixty-six trillion, seven hundred sixty billion, six hundred eighty-six million, eight hundred eighty thousand, four hundred twenty-one".