263309868649 has 2 divisors, whose sum is σ = 263309868650. Its totient is φ = 263309868648.

The previous prime is 263309868643. The next prime is 263309868659. The reversal of 263309868649 is 946868903362.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 254487963024 + 8821905625 = 504468^2 + 93925^2 .

It is a cyclic number.

It is not a de Polignac number, because 263309868649 - 2¹⁵ = 263309835881 is a prime.

It is not a weakly prime, because it can be changed into another prime (263309868643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131654934324 + 131654934325.

It is an arithmetic number, because the mean of its divisors is an integer number (131654934325).

Almost surely, 2^263309868649 is an apocalyptic number.

It is an amenable number.

263309868649 is a deficient number, since it is larger than the sum of its proper divisors (1).

263309868649 is an equidigital number, since it uses as much as digits as its factorization.

263309868649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 80621568, while the sum is 64.

The spelling of 263309868649 in words is "two hundred sixty-three billion, three hundred nine million, eight hundred sixty-eight thousand, six hundred forty-nine".