266256999989 has 2 divisors, whose sum is σ = 266256999990. Its totient is φ = 266256999988.

The previous prime is 266256999979. The next prime is 266257000003. The reversal of 266256999989 is 989999652662.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 202012493764 + 64244506225 = 449458^2 + 253465^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-266256999989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (266256999979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133128499994 + 133128499995.

It is an arithmetic number, because the mean of its divisors is an integer number (133128499995).

Almost surely, 2^266256999989 is an apocalyptic number.

It is an amenable number.

266256999989 is a deficient number, since it is larger than the sum of its proper divisors (1).

266256999989 is an equidigital number, since it uses as much as digits as its factorization.

266256999989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2040733440, while the sum is 80.

The spelling of 266256999989 in words is "two hundred sixty-six billion, two hundred fifty-six million, nine hundred ninety-nine thousand, nine hundred eighty-nine".