6721760640 has 256 divisors, whose sum is σ = 24555985920. Its totient is φ = 1532043264.

The previous prime is 6721760629. The next prime is 6721760641. The reversal of 6721760640 is 460671276.

It is a super-2 number, since 2×6721760640² = 90364132202906419200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6721760641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8695294 + ... + 8696066.

It is an arithmetic number, because the mean of its divisors is an integer number (95921820).

Almost surely, 2^6721760640 is an apocalyptic number.

6721760640 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 6721760640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12277992960).

6721760640 is an abundant number, since it is smaller than the sum of its proper divisors (17834225280).

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

6721760640 is a wasteful number, since it uses less digits than its factorization.

6721760640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1449 (or 1437 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 39.

The square root of 6721760640 is about 81986.3442287800. The cubic root of 6721760640 is about 1887.2423825121.

The spelling of 6721760640 in words is "six billion, seven hundred twenty-one million, seven hundred sixty thousand, six hundred forty".