2565819828 has 240 divisors, whose sum is σ = 7991343360. Its totient is φ = 707616000.

The previous prime is 2565819827. The next prime is 2565819829. The reversal of 2565819828 is 8289185652.

It is a happy number.

2565819828 is a `hidden beast` number, since 2 + 56 + 581 + 9 + 8 + 2 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (2565819827) and next prime (2565819829).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2565819821) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3659878 + ... + 3660578.

It is an arithmetic number, because the mean of its divisors is an integer number (33297264).

Almost surely, 2^2565819828 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 2565819828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3995671680).

2565819828 is an abundant number, since it is smaller than the sum of its proper divisors (5425523532).

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

2565819828 is a wasteful number, since it uses less digits than its factorization.

2565819828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820 (or 809 counting only the distinct ones).

The product of its digits is 2764800, while the sum is 54.

The square root of 2565819828 is about 50653.9221383695. The cubic root of 2565819828 is about 1369.0166150553.

The spelling of 2565819828 in words is "two billion, five hundred sixty-five million, eight hundred nineteen thousand, eight hundred twenty-eight".