649340161 has 2 divisors, whose sum is σ = 649340162. Its totient is φ = 649340160.

The previous prime is 649340129. The next prime is 649340179. The reversal of 649340161 is 161043946.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 431600625 + 217739536 = 20775^2 + 14756^2 .

It is a cyclic number.

It is not a de Polignac number, because 649340161 - 2⁵ = 649340129 is a prime.

It is not a weakly prime, because it can be changed into another prime (649340101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324670080 + 324670081.

It is an arithmetic number, because the mean of its divisors is an integer number (324670081).

Almost surely, 2^649340161 is an apocalyptic number.

It is an amenable number.

649340161 is a deficient number, since it is larger than the sum of its proper divisors (1).

649340161 is an equidigital number, since it uses as much as digits as its factorization.

649340161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 649340161 is about 25482.1537747499. The cubic root of 649340161 is about 865.9458890002.

The spelling of 649340161 in words is "six hundred forty-nine million, three hundred forty thousand, one hundred sixty-one".