2556421266 has 64 divisors (see below), whose sum is σ = 5981045760. Its totient is φ = 713344320.

The previous prime is 2556421249. The next prime is 2556421297. The reversal of 2556421266 is 6621246552.

2556421266 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 385761 + ... + 392331.

It is an arithmetic number, because the mean of its divisors is an integer number (93453840).

Almost surely, 2^2556421266 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2556421266, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2990522880).

2556421266 is an abundant number, since it is smaller than the sum of its proper divisors (3424624494).

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

2556421266 is a wasteful number, since it uses less digits than its factorization.

2556421266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6799.

The product of its digits is 172800, while the sum is 39.

The square root of 2556421266 is about 50561.0647237575. The cubic root of 2556421266 is about 1367.3430070424.

The spelling of 2556421266 in words is "two billion, five hundred fifty-six million, four hundred twenty-one thousand, two hundred sixty-six".