648433981440 has 1152 divisors, whose sum is σ = 2666179152000. Its totient is φ = 145662935040.

The previous prime is 648433981439. The next prime is 648433981457. The reversal of 648433981440 is 44189334846.

648433981440 is a `hidden beast` number, since 6 + 4 + 84 + 33 + 98 + 1 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a super-2 number, since 2×648433981440² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2307594100 + ... + 2307594380.

It is an arithmetic number, because the mean of its divisors is an integer number (2314391625).

Almost surely, 2^648433981440 is an apocalyptic number.

648433981440 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 648433981440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1333089576000).

648433981440 is an abundant number, since it is smaller than the sum of its proper divisors (2017745170560).

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

648433981440 is a wasteful number, since it uses less digits than its factorization.

648433981440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408 (or 371 counting only the distinct ones).

The product of its (nonzero) digits is 7962624, while the sum is 54.

The spelling of 648433981440 in words is "six hundred forty-eight billion, four hundred thirty-three million, nine hundred eighty-one thousand, four hundred forty".