20049989 has 2 divisors, whose sum is σ = 20049990. Its totient is φ = 20049988.

The previous prime is 20049983. The next prime is 20050003. The reversal of 20049989 is 98994002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15880225 + 4169764 = 3985^2 + 2042^2 .

It is a cyclic number.

It is not a de Polignac number, because 20049989 - 2⁴ = 20049973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20049983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10024994 + 10024995.

It is an arithmetic number, because the mean of its divisors is an integer number (10024995).

Almost surely, 2^20049989 is an apocalyptic number.

It is an amenable number.

20049989 is a deficient number, since it is larger than the sum of its proper divisors (1).

20049989 is an equidigital number, since it uses as much as digits as its factorization.

20049989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 20049989 is about 4477.7214071445. The cubic root of 20049989 is about 271.6677252061.

The spelling of 20049989 in words is "twenty million, forty-nine thousand, nine hundred eighty-nine".