620789809 has 2 divisors, whose sum is σ = 620789810. Its totient is φ = 620789808.

The previous prime is 620789791. The next prime is 620789879. The reversal of 620789809 is 908987026.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 363283600 + 257506209 = 19060^2 + 16047^2 .

It is a cyclic number.

It is not a de Polignac number, because 620789809 - 2¹³ = 620781617 is a prime.

It is not a weakly prime, because it can be changed into another prime (620789879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310394904 + 310394905.

It is an arithmetic number, because the mean of its divisors is an integer number (310394905).

Almost surely, 2^620789809 is an apocalyptic number.

It is an amenable number.

620789809 is a deficient number, since it is larger than the sum of its proper divisors (1).

620789809 is an equidigital number, since it uses as much as digits as its factorization.

620789809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 49.

The square root of 620789809 is about 24915.6538946904. The cubic root of 620789809 is about 853.0638262102.

The spelling of 620789809 in words is "six hundred twenty million, seven hundred eighty-nine thousand, eight hundred nine".