2581957764 has 72 divisors (see below), whose sum is σ = 6663384000. Its totient is φ = 842733504.

The previous prime is 2581957751. The next prime is 2581957769. The reversal of 2581957764 is 4677591852.

2581957764 is a `hidden beast` number, since 2 + 5 + 8 + 1 + 9 + 577 + 64 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 2581957764.

It is not an unprimeable number, because it can be changed into a prime (2581957769) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 569097 + ... + 573615.

It is an arithmetic number, because the mean of its divisors is an integer number (92547000).

Almost surely, 2^2581957764 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 2581957764, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3331692000).

2581957764 is an abundant number, since it is smaller than the sum of its proper divisors (4081426236).

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

2581957764 is a wasteful number, since it uses less digits than its factorization.

2581957764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4857 (or 4852 counting only the distinct ones).

The product of its digits is 4233600, while the sum is 54.

The square root of 2581957764 is about 50812.9684627852. The cubic root of 2581957764 is about 1371.8807996524.

The spelling of 2581957764 in words is "two billion, five hundred eighty-one million, nine hundred fifty-seven thousand, seven hundred sixty-four".