7821536411389 has 2 divisors, whose sum is σ = 7821536411390. Its totient is φ = 7821536411388.

The previous prime is 7821536411387. The next prime is 7821536411449. The reversal of 7821536411389 is 9831146351287.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6087653178489 + 1733883232900 = 2467317^2 + 1316770^2 .

It is a cyclic number.

It is not a de Polignac number, because 7821536411389 - 2¹ = 7821536411387 is a prime.

It is a super-2 number, since 2×7821536411389² (a number of 27 digits) contains 22 as substring.

Together with 7821536411387, 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 (7821536411383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3910768205694 + 3910768205695.

It is an arithmetic number, because the mean of its divisors is an integer number (3910768205695).

Almost surely, 2^{7821536411389} is an apocalyptic number.

It is an amenable number.

7821536411389 is a deficient number, since it is larger than the sum of its proper divisors (1).

7821536411389 is an equidigital number, since it uses as much as digits as its factorization.

7821536411389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8709120, while the sum is 58.

The spelling of 7821536411389 in words is "seven trillion, eight hundred twenty-one billion, five hundred thirty-six million, four hundred eleven thousand, three hundred eighty-nine".