866655553 has 2 divisors, whose sum is σ = 866655554. Its totient is φ = 866655552.

The previous prime is 866655541. The next prime is 866655577. The reversal of 866655553 is 355556668.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 462766144 + 403889409 = 21512^2 + 20097^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-866655553 is a prime.

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 866655497 and 866655506.

It is not a weakly prime, because it can be changed into another prime (866655593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433327776 + 433327777.

It is an arithmetic number, because the mean of its divisors is an integer number (433327777).

Almost surely, 2^866655553 is an apocalyptic number.

It is an amenable number.

866655553 is a deficient number, since it is larger than the sum of its proper divisors (1).

866655553 is an equidigital number, since it uses as much as digits as its factorization.

866655553 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3240000, while the sum is 49.

The square root of 866655553 is about 29439.0141309114. The cubic root of 866655553 is about 953.4154265976.

The spelling of 866655553 in words is "eight hundred sixty-six million, six hundred fifty-five thousand, five hundred fifty-three".