11001321261 has 48 divisors (see below), whose sum is σ = 19441164288. Its totient is φ = 6083650800.

The previous prime is 11001321257. The next prime is 11001321311. The reversal of 11001321261 is 16212310011.

It is not a de Polignac number, because 11001321261 - 2² = 11001321257 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11001322261) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 51585 + ... + 157046.

It is an arithmetic number, because the mean of its divisors is an integer number (405024256).

Almost surely, 2^11001321261 is an apocalyptic number.

It is an amenable number.

11001321261 is a deficient number, since it is larger than the sum of its proper divisors (8439843027).

11001321261 is an equidigital number, since it uses as much as digits as its factorization.

11001321261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208684 (or 208672 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 11001321261 its reverse (16212310011), we get a palindrome (27213631272).

The spelling of 11001321261 in words is "eleven billion, one million, three hundred twenty-one thousand, two hundred sixty-one".