649090109 has 2 divisors, whose sum is σ = 649090110. Its totient is φ = 649090108.

The previous prime is 649090097. The next prime is 649090187. The reversal of 649090109 is 901090946.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 531302500 + 117787609 = 23050^2 + 10853^2 .

It is a cyclic number.

It is not a de Polignac number, because 649090109 - 2²⁰ = 648041533 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (649090009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324545054 + 324545055.

It is an arithmetic number, because the mean of its divisors is an integer number (324545055).

Almost surely, 2^649090109 is an apocalyptic number.

It is an amenable number.

649090109 is a deficient number, since it is larger than the sum of its proper divisors (1).

649090109 is an equidigital number, since it uses as much as digits as its factorization.

649090109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 649090109 is about 25477.2468881549. The cubic root of 649090109 is about 865.8347200964.

The spelling of 649090109 in words is "six hundred forty-nine million, ninety thousand, one hundred nine".