206989499491 has 2 divisors, whose sum is σ = 206989499492. Its totient is φ = 206989499490.

The previous prime is 206989499467. The next prime is 206989499531. The reversal of 206989499491 is 194994989602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 206989499491 - 2⁹ = 206989498979 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 206989499491.

It is not a weakly prime, because it can be changed into another prime (206989499191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103494749745 + 103494749746.

It is an arithmetic number, because the mean of its divisors is an integer number (103494749746).

Almost surely, 2^206989499491 is an apocalyptic number.

206989499491 is a deficient number, since it is larger than the sum of its proper divisors (1).

206989499491 is an equidigital number, since it uses as much as digits as its factorization.

206989499491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90699264, while the sum is 70.

The spelling of 206989499491 in words is "two hundred six billion, nine hundred eighty-nine million, four hundred ninety-nine thousand, four hundred ninety-one".