820942877189 has 2 divisors, whose sum is σ = 820942877190. Its totient is φ = 820942877188.

The previous prime is 820942877159. The next prime is 820942877191. The reversal of 820942877189 is 981778249028.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 578230972225 + 242711904964 = 760415^2 + 492658^2 .

It is a cyclic number.

It is not a de Polignac number, because 820942877189 - 2¹⁶ = 820942811653 is a prime.

Together with 820942877191, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (820942877159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410471438594 + 410471438595.

It is an arithmetic number, because the mean of its divisors is an integer number (410471438595).

Almost surely, 2^820942877189 is an apocalyptic number.

It is an amenable number.

820942877189 is a deficient number, since it is larger than the sum of its proper divisors (1).

820942877189 is an equidigital number, since it uses as much as digits as its factorization.

820942877189 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32514048, while the sum is 65.

The spelling of 820942877189 in words is "eight hundred twenty billion, nine hundred forty-two million, eight hundred seventy-seven thousand, one hundred eighty-nine".