20912845663 has 2 divisors, whose sum is σ = 20912845664. Its totient is φ = 20912845662.

The previous prime is 20912845631. The next prime is 20912845693. The reversal of 20912845663 is 36654821902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20912845663 - 2⁵ = 20912845631 is a prime.

It is a super-2 number, since 2×20912845663² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20912845693) 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, 10456422831 + 10456422832.

It is an arithmetic number, because the mean of its divisors is an integer number (10456422832).

Almost surely, 2^20912845663 is an apocalyptic number.

20912845663 is a deficient number, since it is larger than the sum of its proper divisors (1).

20912845663 is an equidigital number, since it uses as much as digits as its factorization.

20912845663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 622080, while the sum is 46.

The spelling of 20912845663 in words is "twenty billion, nine hundred twelve million, eight hundred forty-five thousand, six hundred sixty-three".