821902766917 has 2 divisors, whose sum is σ = 821902766918. Its totient is φ = 821902766916.

The previous prime is 821902766879. The next prime is 821902766957. The reversal of 821902766917 is 719667209128.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 695245786596 + 126656980321 = 833814^2 + 355889^2 .

It is a cyclic number.

It is not a de Polignac number, because 821902766917 - 2¹¹ = 821902764869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (821902766957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 410951383458 + 410951383459.

It is an arithmetic number, because the mean of its divisors is an integer number (410951383459).

Almost surely, 2^821902766917 is an apocalyptic number.

It is an amenable number.

821902766917 is a deficient number, since it is larger than the sum of its proper divisors (1).

821902766917 is an equidigital number, since it uses as much as digits as its factorization.

821902766917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4572288, while the sum is 58.

The spelling of 821902766917 in words is "eight hundred twenty-one billion, nine hundred two million, seven hundred sixty-six thousand, nine hundred seventeen".