2620781664 has 192 divisors, whose sum is σ = 7445716992. Its totient is φ = 805478400.

The previous prime is 2620781627. The next prime is 2620781699. The reversal of 2620781664 is 4661870262.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5734524 + ... + 5734980.

It is an arithmetic number, because the mean of its divisors is an integer number (38779776).

Almost surely, 2^2620781664 is an apocalyptic number.

2620781664 is a gapful number since it is divisible by the number (24) 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 2620781664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3722858496).

2620781664 is an abundant number, since it is smaller than the sum of its proper divisors (4824935328).

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

2620781664 is a wasteful number, since it uses less digits than its factorization.

2620781664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 589 (or 581 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 42.

The square root of 2620781664 is about 51193.5705338082. The cubic root of 2620781664 is about 1378.7227669960.

The spelling of 2620781664 in words is "two billion, six hundred twenty million, seven hundred eighty-one thousand, six hundred sixty-four".