649675409 has 2 divisors, whose sum is σ = 649675410. Its totient is φ = 649675408.

The previous prime is 649675363. The next prime is 649675423. The reversal of 649675409 is 904576946.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 521985409 + 127690000 = 22847^2 + 11300^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-649675409 is a prime.

It is not a weakly prime, because it can be changed into another prime (649675469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324837704 + 324837705.

It is an arithmetic number, because the mean of its divisors is an integer number (324837705).

Almost surely, 2^649675409 is an apocalyptic number.

It is an amenable number.

649675409 is a deficient number, since it is larger than the sum of its proper divisors (1).

649675409 is an equidigital number, since it uses as much as digits as its factorization.

649675409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1632960, while the sum is 50.

The square root of 649675409 is about 25488.7310198056. The cubic root of 649675409 is about 866.0948898364.

The spelling of 649675409 in words is "six hundred forty-nine million, six hundred seventy-five thousand, four hundred nine".