810214208621 has 2 divisors, whose sum is σ = 810214208622. Its totient is φ = 810214208620.

The previous prime is 810214208591. The next prime is 810214208647. The reversal of 810214208621 is 126802412018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 550654527721 + 259559680900 = 742061^2 + 509470^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-810214208621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (810214208021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405107104310 + 405107104311.

It is an arithmetic number, because the mean of its divisors is an integer number (405107104311).

Almost surely, 2^810214208621 is an apocalyptic number.

It is an amenable number.

810214208621 is a deficient number, since it is larger than the sum of its proper divisors (1).

810214208621 is an equidigital number, since it uses as much as digits as its factorization.

810214208621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12288, while the sum is 35.

The spelling of 810214208621 in words is "eight hundred ten billion, two hundred fourteen million, two hundred eight thousand, six hundred twenty-one".