2644581216 has 96 divisors (see below), whose sum is σ = 7439862528. Its totient is φ = 820385280.

The previous prime is 2644581211. The next prime is 2644581241. The reversal of 2644581216 is 6121854462.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2644581211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65511 + ... + 97881.

It is an arithmetic number, because the mean of its divisors is an integer number (77498568).

Almost surely, 2^2644581216 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 2644581216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3719931264).

2644581216 is an abundant number, since it is smaller than the sum of its proper divisors (4795281312).

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

2644581216 is a wasteful number, since it uses less digits than its factorization.

2644581216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32444 (or 32436 counting only the distinct ones).

The product of its digits is 92160, while the sum is 39.

The square root of 2644581216 is about 51425.4918887510. The cubic root of 2644581216 is about 1382.8836320346.

The spelling of 2644581216 in words is "two billion, six hundred forty-four million, five hundred eighty-one thousand, two hundred sixteen".