866486857 has 2 divisors, whose sum is σ = 866486858. Its totient is φ = 866486856.

The previous prime is 866486759. The next prime is 866486869. The reversal of 866486857 is 758684668.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 751911241 + 114575616 = 27421^2 + 10704^2 .

It is a cyclic number.

It is not a de Polignac number, because 866486857 - 2⁷ = 866486729 is a prime.

It is not a weakly prime, because it can be changed into another prime (866486897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433243428 + 433243429.

It is an arithmetic number, because the mean of its divisors is an integer number (433243429).

Almost surely, 2^866486857 is an apocalyptic number.

It is an amenable number.

866486857 is a deficient number, since it is larger than the sum of its proper divisors (1).

866486857 is an equidigital number, since it uses as much as digits as its factorization.

866486857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15482880, while the sum is 58.

The square root of 866486857 is about 29436.1488140008. The cubic root of 866486857 is about 953.3535612636.

The spelling of 866486857 in words is "eight hundred sixty-six million, four hundred eighty-six thousand, eight hundred fifty-seven".