2566639872 has 252 divisors, whose sum is σ = 8143265340. Its totient is φ = 804225024.

The previous prime is 2566639853. The next prime is 2566639903. The reversal of 2566639872 is 2789366652.

It can be written as a sum of positive squares in 2 ways, for example, as 2136658176 + 429981696 = 46224^2 + 20736^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 3172204 + ... + 3173012.

It is an arithmetic number, because the mean of its divisors is an integer number (32314545).

Almost surely, 2^2566639872 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 2566639872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4071632670).

2566639872 is an abundant number, since it is smaller than the sum of its proper divisors (5576625468).

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

2566639872 is an frugal number, since it uses more digits than its factorization.

2566639872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 860 (or 831 counting only the distinct ones).

The product of its digits is 6531840, while the sum is 54.

The square root of 2566639872 is about 50662.0160672668. The cubic root of 2566639872 is about 1369.1624468435.

Subtracting from 2566639872 its product of digits (6531840), we obtain a cube (2560108032 = 1368³).

The spelling of 2566639872 in words is "two billion, five hundred sixty-six million, six hundred thirty-nine thousand, eight hundred seventy-two".