21253246605623 has 2 divisors, whose sum is σ = 21253246605624. Its totient is φ = 21253246605622.

The previous prime is 21253246605607. The next prime is 21253246605649. The reversal of 21253246605623 is 32650664235212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21253246605623 - 2⁴ = 21253246605607 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21253246605683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10626623302811 + 10626623302812.

It is an arithmetic number, because the mean of its divisors is an integer number (10626623302812).

Almost surely, 2^{21253246605623} is an apocalyptic number.

21253246605623 is a deficient number, since it is larger than the sum of its proper divisors (1).

21253246605623 is an equidigital number, since it uses as much as digits as its factorization.

21253246605623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3110400, while the sum is 47.

The spelling of 21253246605623 in words is "twenty-one trillion, two hundred fifty-three billion, two hundred forty-six million, six hundred five thousand, six hundred twenty-three".