648681444 has 36 divisors (see below), whose sum is σ = 1736178444. Its totient is φ = 203507712.

The previous prime is 648681419. The next prime is 648681463. The reversal of 648681444 is 444186846.

648681444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 319694400 + 328987044 = 17880^2 + 18138^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 648681444.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 529357 + ... + 530580.

It is an arithmetic number, because the mean of its divisors is an integer number (48227179).

Almost surely, 2^648681444 is an apocalyptic number.

It is an amenable number.

648681444 is an abundant number, since it is smaller than the sum of its proper divisors (1087497000).

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

648681444 is a wasteful number, since it uses less digits than its factorization.

648681444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059964 (or 1059959 counting only the distinct ones).

The product of its digits is 589824, while the sum is 45.

The square root of 648681444 is about 25469.2254299184. The cubic root of 648681444 is about 865.6529730502.

The spelling of 648681444 in words is "six hundred forty-eight million, six hundred eighty-one thousand, four hundred forty-four".