647266889 has 2 divisors, whose sum is σ = 647266890. Its totient is φ = 647266888.

The previous prime is 647266847. The next prime is 647266927. The reversal of 647266889 is 988662746.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 591316489 + 55950400 = 24317^2 + 7480^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647266889 is a prime.

It is not a weakly prime, because it can be changed into another prime (647266819) 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, 323633444 + 323633445.

It is an arithmetic number, because the mean of its divisors is an integer number (323633445).

Almost surely, 2^647266889 is an apocalyptic number.

It is an amenable number.

647266889 is a deficient number, since it is larger than the sum of its proper divisors (1).

647266889 is an equidigital number, since it uses as much as digits as its factorization.

647266889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6967296, while the sum is 56.

The square root of 647266889 is about 25441.4403876825. The cubic root of 647266889 is about 865.0232829221.

The spelling of 647266889 in words is "six hundred forty-seven million, two hundred sixty-six thousand, eight hundred eighty-nine".