2565783864 has 240 divisors, whose sum is σ = 8801951400. Its totient is φ = 694334592.

The previous prime is 2565783859. The next prime is 2565783877. The reversal of 2565783864 is 4683875652.

2565783864 is a `hidden beast` number, since 2 + 5 + 6 + 578 + 3 + 8 + 64 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 2565783864.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 601162 + ... + 605414.

Almost surely, 2^2565783864 is an apocalyptic number.

2565783864 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 2565783864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4400975700).

2565783864 is an abundant number, since it is smaller than the sum of its proper divisors (6236167536).

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

2565783864 is a wasteful number, since it uses less digits than its factorization.

2565783864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4304 (or 4284 counting only the distinct ones).

The product of its digits is 9676800, while the sum is 54.

The square root of 2565783864 is about 50653.5671399360. The cubic root of 2565783864 is about 1369.0102187185.

The spelling of 2565783864 in words is "two billion, five hundred sixty-five million, seven hundred eighty-three thousand, eight hundred sixty-four".