6511521623 has 2 divisors, whose sum is σ = 6511521624. Its totient is φ = 6511521622.

The previous prime is 6511521617. The next prime is 6511521637. The reversal of 6511521623 is 3261251156.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6511521623 - 2¹⁰ = 6511520599 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6511521623.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6511524623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3255760811 + 3255760812.

It is an arithmetic number, because the mean of its divisors is an integer number (3255760812).

Almost surely, 2^6511521623 is an apocalyptic number.

6511521623 is a deficient number, since it is larger than the sum of its proper divisors (1).

6511521623 is an equidigital number, since it uses as much as digits as its factorization.

6511521623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10800, while the sum is 32.

The square root of 6511521623 is about 80693.9999194488. Note that the first 4 decimals coincide. The cubic root of 6511521623 is about 1867.3576092296.

Adding to 6511521623 its reverse (3261251156), we get a palindrome (9772772779).

The spelling of 6511521623 in words is "six billion, five hundred eleven million, five hundred twenty-one thousand, six hundred twenty-three".