634535809 has 2 divisors, whose sum is σ = 634535810. Its totient is φ = 634535808.

The previous prime is 634535791. The next prime is 634535813. The reversal of 634535809 is 908535436.

634535809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 577200625 + 57335184 = 24025^2 + 7572^2 .

It is a cyclic number.

It is not a de Polignac number, because 634535809 - 2¹³ = 634527617 is a prime.

It is not a weakly prime, because it can be changed into another prime (634535849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 317267904 + 317267905.

It is an arithmetic number, because the mean of its divisors is an integer number (317267905).

Almost surely, 2^634535809 is an apocalyptic number.

It is an amenable number.

634535809 is a deficient number, since it is larger than the sum of its proper divisors (1).

634535809 is an equidigital number, since it uses as much as digits as its factorization.

634535809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 388800, while the sum is 43.

The square root of 634535809 is about 25189.9942238977. The cubic root of 634535809 is about 859.3143123716.

The spelling of 634535809 in words is "six hundred thirty-four million, five hundred thirty-five thousand, eight hundred nine".