8212840396909 has 2 divisors, whose sum is σ = 8212840396910. Its totient is φ = 8212840396908.

The previous prime is 8212840396907. The next prime is 8212840396991. The reversal of 8212840396909 is 9096930482128.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7986292956009 + 226547440900 = 2826003^2 + 475970^2 .

It is a cyclic number.

It is not a de Polignac number, because 8212840396909 - 2¹ = 8212840396907 is a prime.

Together with 8212840396907, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8212840396907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4106420198454 + 4106420198455.

It is an arithmetic number, because the mean of its divisors is an integer number (4106420198455).

Almost surely, 2^{8212840396909} is an apocalyptic number.

It is an amenable number.

8212840396909 is a deficient number, since it is larger than the sum of its proper divisors (1).

8212840396909 is an equidigital number, since it uses as much as digits as its factorization.

8212840396909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13436928, while the sum is 61.

The spelling of 8212840396909 in words is "eight trillion, two hundred twelve billion, eight hundred forty million, three hundred ninety-six thousand, nine hundred nine".