1191285225 has 135 divisors (see below), whose sum is σ = 2430659253. Its totient is φ = 576538560.

The previous prime is 1191285181. The next prime is 1191285239. The reversal of 1191285225 is 5225821911.

The square root of 1191285225 is 34515.

It is a perfect power (a square), and thus also a powerful number.

1191285225 is a `hidden beast` number, since 1 + 1 + 9 + 128 + 522 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 307055529 + 884229696 = 17523^2 + 29736^2 .

It is a tau number, because it is divible by the number of its divisors (135).

It is not a de Polignac number, because 1191285225 - 2⁷ = 1191285097 is a prime.

Its product of digits (14400) is a multiple of the sum of its prime divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 1191285225.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 20191246 + ... + 20191304.

Almost surely, 2^1191285225 is an apocalyptic number.

1191285225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1191285225 is the 34515-th square number.

1191285225 is the 17258-th centered octagonal number.

It is an amenable number.

1191285225 is an abundant number, since it is smaller than the sum of its proper divisors (1239374028).

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

1191285225 is an equidigital number, since it uses as much as digits as its factorization.

1191285225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166 (or 80 counting only the distinct ones).

The product of its digits is 14400, while the sum is 36.

The cubic root of 1191285225 is about 1060.0798637465.

Multiplying 1191285225 by its sum of digits (36), we get a square (42886268100 = 207090²).

Multiplying 1191285225 by its product of digits (14400), we get a square (17154507240000 = 4141800²).

The spelling of 1191285225 in words is "one billion, one hundred ninety-one million, two hundred eighty-five thousand, two hundred twenty-five".