2644556040 has 640 divisors, whose sum is σ = 11353478400. Its totient is φ = 538970112.

The previous prime is 2644556027. The next prime is 2644556041. The reversal of 2644556040 is 406554462.

2644556040 is a `hidden beast` number, since 2 + 6 + 4 + 45 + 5 + 604 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2644555986 and 2644556004.

It is not an unprimeable number, because it can be changed into a prime (2644556041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 139187151 + ... + 139187169.

It is an arithmetic number, because the mean of its divisors is an integer number (17739810).

Almost surely, 2^2644556040 is an apocalyptic number.

2644556040 is a gapful number since it is divisible by the number (20) 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 2644556040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5676739200).

2644556040 is an abundant number, since it is smaller than the sum of its proper divisors (8708922360).

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

2644556040 is a wasteful number, since it uses less digits than its factorization.

2644556040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 36.

The square root of 2644556040 is about 51425.2471068443. The cubic root of 2644556040 is about 1382.8792437420.

The spelling of 2644556040 in words is "two billion, six hundred forty-four million, five hundred fifty-six thousand, forty".