6549128865440 has 384 divisors, whose sum is σ = 18782959104000. Its totient is φ = 2109275283456.

The previous prime is 6549128865437. The next prime is 6549128865443. The reversal of 6549128865440 is 445688219456.

It is an interprime number because it is at equal distance from previous prime (6549128865437) and next prime (6549128865443).

It is a super-2 number, since 2×6549128865440² (a number of 26 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6549128865443) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2399825996 + ... + 2399828724.

It is an arithmetic number, because the mean of its divisors is an integer number (48913956000).

Almost surely, 2^{6549128865440} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6549128865440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9391479552000).

6549128865440 is an abundant number, since it is smaller than the sum of its proper divisors (12233830238560).

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

6549128865440 is a wasteful number, since it uses less digits than its factorization.

6549128865440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4412 (or 4404 counting only the distinct ones).

The product of its (nonzero) digits is 66355200, while the sum is 62.

The spelling of 6549128865440 in words is "six trillion, five hundred forty-nine billion, one hundred twenty-eight million, eight hundred sixty-five thousand, four hundred forty".