2556421265 has 4 divisors (see below), whose sum is σ = 3067705524. Its totient is φ = 2045137008.

The previous prime is 2556421249. The next prime is 2556421297. The reversal of 2556421265 is 5621246552.

It is a happy number.

2556421265 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 645769744 + 1910651521 = 25412^2 + 43711^2 .

It is a cyclic number.

It is not a de Polignac number, because 2556421265 - 2⁴ = 2556421249 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 255642122 + ... + 255642131.

It is an arithmetic number, because the mean of its divisors is an integer number (766926381).

Almost surely, 2^2556421265 is an apocalyptic number.

It is an amenable number.

2556421265 is a deficient number, since it is larger than the sum of its proper divisors (511284259).

2556421265 is an equidigital number, since it uses as much as digits as its factorization.

2556421265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 511284258.

The product of its digits is 144000, while the sum is 38.

The square root of 2556421265 is about 50561.0647138685. The cubic root of 2556421265 is about 1367.3430068641.

The spelling of 2556421265 in words is "two billion, five hundred fifty-six million, four hundred twenty-one thousand, two hundred sixty-five".