866653189 has 2 divisors, whose sum is σ = 866653190. Its totient is φ = 866653188.

The previous prime is 866653187. The next prime is 866653201. The reversal of 866653189 is 981356668.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 609596100 + 257057089 = 24690^2 + 16033^2 .

It is a cyclic number.

It is not a de Polignac number, because 866653189 - 2¹ = 866653187 is a prime.

Together with 866653187, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866653187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433326594 + 433326595.

It is an arithmetic number, because the mean of its divisors is an integer number (433326595).

Almost surely, 2^866653189 is an apocalyptic number.

It is an amenable number.

866653189 is a deficient number, since it is larger than the sum of its proper divisors (1).

866653189 is an equidigital number, since it uses as much as digits as its factorization.

866653189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1866240, while the sum is 52.

The square root of 866653189 is about 29438.9739800829. The cubic root of 866653189 is about 953.4145597110.

The spelling of 866653189 in words is "eight hundred sixty-six million, six hundred fifty-three thousand, one hundred eighty-nine".