1265221260 has 144 divisors (see below), whose sum is σ = 4240506816. Its totient is φ = 303722496.

The previous prime is 1265221249. The next prime is 1265221289. The reversal of 1265221260 is 621225621.

1265221260 is a `hidden beast` number, since 1 + 2 + 652 + 2 + 1 + 2 + 6 + 0 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 61392 + ... + 79368.

It is an arithmetic number, because the mean of its divisors is an integer number (29447964).

Almost surely, 2^1265221260 is an apocalyptic number.

1265221260 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1265221260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2120253408).

1265221260 is an abundant number, since it is smaller than the sum of its proper divisors (2975285556).

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

1265221260 is a wasteful number, since it uses less digits than its factorization.

1265221260 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18032 (or 18027 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 1265221260 is about 35569.9488332497. The cubic root of 1265221260 is about 1081.5721444919.

Adding to 1265221260 its reverse (621225621), we get a palindrome (1886446881).

The spelling of 1265221260 in words is "one billion, two hundred sixty-five million, two hundred twenty-one thousand, two hundred sixty".