2644761840 has 160 divisors (see below), whose sum is σ = 9385351680. Its totient is φ = 603528192.

The previous prime is 2644761817. The next prime is 2644761841. The reversal of 2644761840 is 481674462.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 2644761792 and 2644761801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2644761841) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1674171 + ... + 1675749.

It is an arithmetic number, because the mean of its divisors is an integer number (58658448).

Almost surely, 2^2644761840 is an apocalyptic number.

2644761840 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 2644761840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4692675840).

2644761840 is an abundant number, since it is smaller than the sum of its proper divisors (6740589840).

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

2644761840 is a wasteful number, since it uses less digits than its factorization.

2644761840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2599 (or 2593 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 42.

The square root of 2644761840 is about 51427.2480305917. The cubic root of 2644761840 is about 1382.9151148122.

The spelling of 2644761840 in words is "two billion, six hundred forty-four million, seven hundred sixty-one thousand, eight hundred forty".