649340129 has 2 divisors, whose sum is σ = 649340130. Its totient is φ = 649340128.

The previous prime is 649340123. The next prime is 649340161. The reversal of 649340129 is 921043946.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 367872400 + 281467729 = 19180^2 + 16777^2 .

It is a cyclic number.

It is not a de Polignac number, because 649340129 - 2⁴ = 649340113 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 649340092 and 649340101.

It is not a weakly prime, because it can be changed into another prime (649340123) 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, 324670064 + 324670065.

It is an arithmetic number, because the mean of its divisors is an integer number (324670065).

Almost surely, 2^649340129 is an apocalyptic number.

It is an amenable number.

649340129 is a deficient number, since it is larger than the sum of its proper divisors (1).

649340129 is an equidigital number, since it uses as much as digits as its factorization.

649340129 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 38.

The square root of 649340129 is about 25482.1531468595. The cubic root of 649340129 is about 865.9458747754.

The spelling of 649340129 in words is "six hundred forty-nine million, three hundred forty thousand, one hundred twenty-nine".