1261221248 has 32 divisors (see below), whose sum is σ = 2871532560. Its totient is φ = 540523008.

The previous prime is 1261221217. The next prime is 1261221251. The reversal of 1261221248 is 8421221621.

It is a tau number, because it is divible by the number of its divisors (32).

It is a self number, because there is not a number n which added to its sum of digits gives 1261221248.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 702911 + ... + 704702.

Almost surely, 2^1261221248 is an apocalyptic number.

It is an amenable number.

1261221248 is an abundant number, since it is smaller than the sum of its proper divisors (1610311312).

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

1261221248 is an equidigital number, since it uses as much as digits as its factorization.

1261221248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1407634 (or 1407622 counting only the distinct ones).

The product of its digits is 3072, while the sum is 29.

The square root of 1261221248 is about 35513.6769146761. The cubic root of 1261221248 is about 1080.4311401642.

Adding to 1261221248 its reverse (8421221621), we get a palindrome (9682442869).

The spelling of 1261221248 in words is "one billion, two hundred sixty-one million, two hundred twenty-one thousand, two hundred forty-eight".