865099816849 has 2 divisors, whose sum is σ = 865099816850. Its totient is φ = 865099816848.

The previous prime is 865099816751. The next prime is 865099816949. The reversal of 865099816849 is 948618990568.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 668502464400 + 196597352449 = 817620^2 + 443393^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-865099816849 is a prime.

It is a super-2 number, since 2×865099816849² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (865099816349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 432549908424 + 432549908425.

It is an arithmetic number, because the mean of its divisors is an integer number (432549908425).

Almost surely, 2^865099816849 is an apocalyptic number.

It is an amenable number.

865099816849 is a deficient number, since it is larger than the sum of its proper divisors (1).

865099816849 is an equidigital number, since it uses as much as digits as its factorization.

865099816849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 268738560, while the sum is 73.

The spelling of 865099816849 in words is "eight hundred sixty-five billion, ninety-nine million, eight hundred sixteen thousand, eight hundred forty-nine".