866704549 has 2 divisors, whose sum is σ = 866704550. Its totient is φ = 866704548.

The previous prime is 866704519. The next prime is 866704567. The reversal of 866704549 is 945407668.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 707187649 + 159516900 = 26593^2 + 12630^2 .

It is a cyclic number.

It is not a de Polignac number, because 866704549 - 2²¹ = 864607397 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866704519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433352274 + 433352275.

It is an arithmetic number, because the mean of its divisors is an integer number (433352275).

Almost surely, 2^866704549 is an apocalyptic number.

It is an amenable number.

866704549 is a deficient number, since it is larger than the sum of its proper divisors (1).

866704549 is an equidigital number, since it uses as much as digits as its factorization.

866704549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1451520, while the sum is 49.

The square root of 866704549 is about 29439.8462801693. The cubic root of 866704549 is about 953.4333932364.

It can be divided in two parts, 86670 and 4549, that added together give a palindrome (91219).

The spelling of 866704549 in words is "eight hundred sixty-six million, seven hundred four thousand, five hundred forty-nine".