20919986071 has 2 divisors, whose sum is σ = 20919986072. Its totient is φ = 20919986070.

The previous prime is 20919986033. The next prime is 20919986137. The reversal of 20919986071 is 17068991902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20919986071 - 2¹³ = 20919977879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20919986671) 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, 10459993035 + 10459993036.

It is an arithmetic number, because the mean of its divisors is an integer number (10459993036).

Almost surely, 2^20919986071 is an apocalyptic number.

20919986071 is a deficient number, since it is larger than the sum of its proper divisors (1).

20919986071 is an equidigital number, since it uses as much as digits as its factorization.

20919986071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 489888, while the sum is 52.

The spelling of 20919986071 in words is "twenty billion, nine hundred nineteen million, nine hundred eighty-six thousand, seventy-one".