649632169 has 4 divisors (see below), whose sum is σ = 687845844. Its totient is φ = 611418496.

The previous prime is 649632163. The next prime is 649632197. The reversal of 649632169 is 961236946.

649632169 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 555309225 + 94322944 = 23565^2 + 9712^2 .

It is a cyclic number.

It is not a de Polignac number, because 649632169 - 2⁹ = 649631657 is a prime.

It is a super-2 number, since 2×649632169² = 844043909999289122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (649632163) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19106812 + ... + 19106845.

It is an arithmetic number, because the mean of its divisors is an integer number (171961461).

Almost surely, 2^649632169 is an apocalyptic number.

It is an amenable number.

649632169 is a deficient number, since it is larger than the sum of its proper divisors (38213675).

649632169 is a wasteful number, since it uses less digits than its factorization.

649632169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38213674.

The product of its digits is 419904, while the sum is 46.

The square root of 649632169 is about 25487.8827877091. The cubic root of 649632169 is about 866.0756747159.

The spelling of 649632169 in words is "six hundred forty-nine million, six hundred thirty-two thousand, one hundred sixty-nine".