2128581225 has 36 divisors (see below), whose sum is σ = 3818462076. Its totient is φ = 1133475840.

The previous prime is 2128581199. The next prime is 2128581233. The reversal of 2128581225 is 5221858212.

It can be written as a sum of positive squares in 6 ways, for example, as 549949401 + 1578631824 = 23451^2 + 39732^2 .

It is not a de Polignac number, because 2128581225 - 2¹⁹ = 2128056937 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2128581225.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 144397 + ... + 158453.

It is an arithmetic number, because the mean of its divisors is an integer number (106068391).

Almost surely, 2^2128581225 is an apocalyptic number.

2128581225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2128581225 is a deficient number, since it is larger than the sum of its proper divisors (1689880851).

2128581225 is a wasteful number, since it uses less digits than its factorization.

2128581225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14746 (or 14738 counting only the distinct ones).

The product of its digits is 25600, while the sum is 36.

The square root of 2128581225 is about 46136.5497734714. The cubic root of 2128581225 is about 1286.3626125738.

The spelling of 2128581225 in words is "two billion, one hundred twenty-eight million, five hundred eighty-one thousand, two hundred twenty-five".