20726789 has 2 divisors, whose sum is σ = 20726790. Its totient is φ = 20726788.

The previous prime is 20726779. The next prime is 20726801. The reversal of 20726789 is 98762702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16337764 + 4389025 = 4042^2 + 2095^2 .

It is a cyclic number.

It is not a de Polignac number, because 20726789 - 2⁴ = 20726773 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20726779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10363394 + 10363395.

It is an arithmetic number, because the mean of its divisors is an integer number (10363395).

Almost surely, 2^20726789 is an apocalyptic number.

It is an amenable number.

20726789 is a deficient number, since it is larger than the sum of its proper divisors (1).

20726789 is an equidigital number, since it uses as much as digits as its factorization.

20726789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84672, while the sum is 41.

The square root of 20726789 is about 4552.6683384582. The cubic root of 20726789 is about 274.6907333189.

The spelling of 20726789 in words is "twenty million, seven hundred twenty-six thousand, seven hundred eighty-nine".