649656 has 48 divisors (see below), whose sum is σ = 2012400. Its totient is φ = 185472.

The previous prime is 649651. The next prime is 649657. The reversal of 649656 is 656946.

649656 = T₃₉₉ + T₄₀₀ + ... + T₄₀₆.

It is a happy number.

649656 is a `hidden beast` number, since 649 + 6 + 5 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 649656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649651) by changing a digit.

649656 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 in 11 ways as a sum of consecutive naturals, for example, 141 + ... + 1148.

It is an arithmetic number, because the mean of its divisors is an integer number (41925).

2⁶⁴⁹⁶⁵⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1006200).

649656 is an abundant number, since it is smaller than the sum of its proper divisors (1362744).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

649656 is a wasteful number, since it uses less digits than its factorization.

649656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1308 (or 1301 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The square root of 649656 is about 806.0124068524. The cubic root of 649656 is about 86.6086264912.

The spelling of 649656 in words is "six hundred forty-nine thousand, six hundred fifty-six".