649040 has 80 divisors (see below), whose sum is σ = 1845120. Its totient is φ = 207360.

The previous prime is 649039. The next prime is 649063. The reversal of 649040 is 40946.

649040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 648997 and 649015.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10610 + ... + 10670.

It is an arithmetic number, because the mean of its divisors is an integer number (23064).

2⁶⁴⁹⁰⁴⁰ 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 649040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (922560).

649040 is an abundant number, since it is smaller than the sum of its proper divisors (1196080).

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

649040 is a wasteful number, since it uses less digits than its factorization.

649040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100 (or 94 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 649040 is about 805.6301881136. The cubic root of 649040 is about 86.5812439046.

Adding to 649040 its reverse (40946), we get a palindrome (689986).

The spelling of 649040 in words is "six hundred forty-nine thousand, forty".