20641623599 has 2 divisors, whose sum is σ = 20641623600. Its totient is φ = 20641623598.

The previous prime is 20641623589. The next prime is 20641623623. The reversal of 20641623599 is 99532614602.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20641623599 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20641623559) 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, 10320811799 + 10320811800.

It is an arithmetic number, because the mean of its divisors is an integer number (10320811800).

Almost surely, 2^20641623599 is an apocalyptic number.

20641623599 is a deficient number, since it is larger than the sum of its proper divisors (1).

20641623599 is an equidigital number, since it uses as much as digits as its factorization.

20641623599 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 699840, while the sum is 47.

The spelling of 20641623599 in words is "twenty billion, six hundred forty-one million, six hundred twenty-three thousand, five hundred ninety-nine".