6544645380 has 576 divisors, whose sum is σ = 27254223360. Its totient is φ = 1230225408.

The previous prime is 6544645379. The next prime is 6544645381. The reversal of 6544645380 is 835464456.

6544645380 is a `hidden beast` number, since 6 + 54 + 4 + 64 + 538 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (6544645379) and next prime (6544645381).

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

It is not an unprimeable number, because it can be changed into a prime (6544645381) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 5290122 + ... + 5291358.

It is an arithmetic number, because the mean of its divisors is an integer number (47316360).

Almost surely, 2^6544645380 is an apocalyptic number.

6544645380 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 6544645380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13627111680).

6544645380 is an abundant number, since it is smaller than the sum of its proper divisors (20709577980).

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

6544645380 is a wasteful number, since it uses less digits than its factorization.

6544645380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1308 (or 1303 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 45.

The square root of 6544645380 is about 80898.9825646775. The cubic root of 6544645380 is about 1870.5186375414.

The spelling of 6544645380 in words is "six billion, five hundred forty-four million, six hundred forty-five thousand, three hundred eighty".