651444640 has 384 divisors, whose sum is σ = 2125025280. Its totient is φ = 183997440.

The previous prime is 651444623. The next prime is 651444691. The reversal of 651444640 is 46444156.

It is a junction number, because it is equal to n+sod(n) for n = 651444596 and 651444605.

It is an unprimeable 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 63 ways as a sum of consecutive naturals, for example, 28323669 + ... + 28323691.

It is an arithmetic number, because the mean of its divisors is an integer number (5533920).

Almost surely, 2^651444640 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 651444640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1062512640).

651444640 is an abundant number, since it is smaller than the sum of its proper divisors (1473580640).

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

651444640 is a wasteful number, since it uses less digits than its factorization.

651444640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 67 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 34.

The square root of 651444640 is about 25523.4135648036. The cubic root of 651444640 is about 866.8803759629.

Adding to 651444640 its reverse (46444156), we get a palindrome (697888796).

The spelling of 651444640 in words is "six hundred fifty-one million, four hundred forty-four thousand, six hundred forty".