7811520006643 has 2 divisors, whose sum is σ = 7811520006644. Its totient is φ = 7811520006642.

The previous prime is 7811520006623. The next prime is 7811520006673. The reversal of 7811520006643 is 3466000251187.

It is a weak prime.

It is an emirp because it is prime and its reverse (3466000251187) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7811520006643 - 2¹⁷ = 7811519875571 is a prime.

It is a super-2 number, since 2×7811520006643² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 7811520006643.

It is not a weakly prime, because it can be changed into another prime (7811520006623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3905760003321 + 3905760003322.

It is an arithmetic number, because the mean of its divisors is an integer number (3905760003322).

Almost surely, 2^{7811520006643} is an apocalyptic number.

7811520006643 is a deficient number, since it is larger than the sum of its proper divisors (1).

7811520006643 is an equidigital number, since it uses as much as digits as its factorization.

7811520006643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 241920, while the sum is 43.

The spelling of 7811520006643 in words is "seven trillion, eight hundred eleven billion, five hundred twenty million, six thousand, six hundred forty-three".