648540640 has 144 divisors (see below), whose sum is σ = 1703283120. Its totient is φ = 233164800.

The previous prime is 648540619. The next prime is 648540649. The reversal of 648540640 is 46045846.

It is a self number, because there is not a number n which added to its sum of digits gives 648540640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648540649) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2690920 + ... + 2691160.

It is an arithmetic number, because the mean of its divisors is an integer number (11828355).

Almost surely, 2^648540640 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 648540640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (851641560).

648540640 is an abundant number, since it is smaller than the sum of its proper divisors (1054742480).

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

648540640 is a wasteful number, since it uses less digits than its factorization.

648540640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417 (or 398 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 37.

The square root of 648540640 is about 25466.4610811946. The cubic root of 648540640 is about 865.5903351035.

The spelling of 648540640 in words is "six hundred forty-eight million, five hundred forty thousand, six hundred forty".