20989523759 has 2 divisors, whose sum is σ = 20989523760. Its totient is φ = 20989523758.

The previous prime is 20989523743. The next prime is 20989523831. The reversal of 20989523759 is 95732598902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20989523759 - 2⁴ = 20989523743 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 20989523698 and 20989523707.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20989523729) 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, 10494761879 + 10494761880.

It is an arithmetic number, because the mean of its divisors is an integer number (10494761880).

Almost surely, 2^20989523759 is an apocalyptic number.

20989523759 is a deficient number, since it is larger than the sum of its proper divisors (1).

20989523759 is an equidigital number, since it uses as much as digits as its factorization.

20989523759 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12247200, while the sum is 59.

The spelling of 20989523759 in words is "twenty billion, nine hundred eighty-nine million, five hundred twenty-three thousand, seven hundred fifty-nine".