648393721920 has 672 divisors, whose sum is σ = 2587297579776. Its totient is φ = 145981440000.

The previous prime is 648393721909. The next prime is 648393721931. The reversal of 648393721920 is 29127393846.

648393721920 is a `hidden beast` number, since 6 + 4 + 83 + 9 + 372 + 192 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (648393721909) and next prime (648393721931).

It is a tau number, because it is divible by the number of its divisors (672).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 490834860 + ... + 490836180.

It is an arithmetic number, because the mean of its divisors is an integer number (3850145208).

Almost surely, 2^648393721920 is an apocalyptic number.

648393721920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 648393721920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1293648789888).

648393721920 is an abundant number, since it is smaller than the sum of its proper divisors (1938903857856).

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

648393721920 is a wasteful number, since it uses less digits than its factorization.

648393721920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1699 (or 1686 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 54.

The spelling of 648393721920 in words is "six hundred forty-eight billion, three hundred ninety-three million, seven hundred twenty-one thousand, nine hundred twenty".