6645649177440 has 1536 divisors, whose sum is σ = 29149982023680. Its totient is φ = 1376737689600.

The previous prime is 6645649177421. The next prime is 6645649177459. The reversal of 6645649177440 is 447719465466.

6645649177440 is a `hidden beast` number, since 6 + 6 + 45 + 64 + 91 + 7 + 7 + 440 = 666.

It is an interprime number because it is at equal distance from previous prime (6645649177421) and next prime (6645649177459).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 12755564380 + ... + 12755564900.

It is an arithmetic number, because the mean of its divisors is an integer number (18977852880).

Almost surely, 2^{6645649177440} is an apocalyptic number.

6645649177440 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 6645649177440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14574991011840).

6645649177440 is an abundant number, since it is smaller than the sum of its proper divisors (22504332846240).

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

6645649177440 is a wasteful number, since it uses less digits than its factorization.

6645649177440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1093 (or 1079 counting only the distinct ones).

The product of its (nonzero) digits is 121927680, while the sum is 63.

The spelling of 6645649177440 in words is "six trillion, six hundred forty-five billion, six hundred forty-nine million, one hundred seventy-seven thousand, four hundred forty".