6641720236800 has 864 divisors, whose sum is σ = 26676325105920. Its totient is φ = 1603584000000.

The previous prime is 6641720236757. The next prime is 6641720236843. The reversal of 6641720236800 is 86320271466.

It is an interprime number because it is at equal distance from previous prime (6641720236757) and next prime (6641720236843).

It is a tau number, because it is divible by the number of its divisors (864).

It is a super-2 number, since 2×6641720236800² (a number of 26 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 477093840 + ... + 477107760.

It is an arithmetic number, because the mean of its divisors is an integer number (30875376280).

Almost surely, 2^{6641720236800} is an apocalyptic number.

6641720236800 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 6641720236800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13338162552960).

6641720236800 is an abundant number, since it is smaller than the sum of its proper divisors (20034604869120).

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

6641720236800 is a wasteful number, since it uses less digits than its factorization.

6641720236800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14218 (or 14193 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 45.

The spelling of 6641720236800 in words is "six trillion, six hundred forty-one billion, seven hundred twenty million, two hundred thirty-six thousand, eight hundred".