8640553440 has 48 divisors (see below), whose sum is σ = 27217744848. Its totient is φ = 2304147456.

The previous prime is 8640553409. The next prime is 8640553457. The reversal of 8640553440 is 443550468.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9000097 + ... + 9001056.

It is an arithmetic number, because the mean of its divisors is an integer number (567036351).

Almost surely, 2^8640553440 is an apocalyptic number.

8640553440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

8640553440 is an abundant number, since it is smaller than the sum of its proper divisors (18577191408).

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

8640553440 is a wasteful number, since it uses less digits than its factorization.

8640553440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18001171 (or 18001163 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 39.

The square root of 8640553440 is about 92954.5772945044. The cubic root of 8640553440 is about 2052.0149484603.

The spelling of 8640553440 in words is "eight billion, six hundred forty million, five hundred fifty-three thousand, four hundred forty".