625766909 has 2 divisors, whose sum is σ = 625766910. Its totient is φ = 625766908.

The previous prime is 625766893. The next prime is 625766927. The reversal of 625766909 is 909667526.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 529138009 + 96628900 = 23003^2 + 9830^2 .

It is a cyclic number.

It is not a de Polignac number, because 625766909 - 2⁴ = 625766893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (625766809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312883454 + 312883455.

It is an arithmetic number, because the mean of its divisors is an integer number (312883455).

Almost surely, 2^625766909 is an apocalyptic number.

It is an amenable number.

625766909 is a deficient number, since it is larger than the sum of its proper divisors (1).

625766909 is an equidigital number, since it uses as much as digits as its factorization.

625766909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1224720, while the sum is 50.

The square root of 625766909 is about 25015.3334776892. Note that the first 3 decimals coincide. The cubic root of 625766909 is about 855.3375359847.

The spelling of 625766909 in words is "six hundred twenty-five million, seven hundred sixty-six thousand, nine hundred nine".