649988064 has 336 divisors, whose sum is σ = 2231031600. Its totient is φ = 184135680.

The previous prime is 649988057. The next prime is 649988069. The reversal of 649988064 is 460889946.

649988064 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 649988064.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649988069) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 4362262 + ... + 4362410.

It is an arithmetic number, because the mean of its divisors is an integer number (6639975).

Almost surely, 2^649988064 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 649988064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1115515800).

649988064 is an abundant number, since it is smaller than the sum of its proper divisors (1581043536).

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

649988064 is a wasteful number, since it uses less digits than its factorization.

649988064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The square root of 649988064 is about 25494.8634826704. The cubic root of 649988064 is about 866.2338030367.

The spelling of 649988064 in words is "six hundred forty-nine million, nine hundred eighty-eight thousand, sixty-four".