11721291 has 4 divisors (see below), whose sum is σ = 15628392. Its totient is φ = 7814192.

The previous prime is 11721289. The next prime is 11721293. The reversal of 11721291 is 19212711.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (11721289) and next prime (11721293).

It is a cyclic number.

It is not a de Polignac number, because 11721291 - 2¹ = 11721289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11721293) by changing a digit.

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, 1953546 + ... + 1953551.

It is an arithmetic number, because the mean of its divisors is an integer number (3907098).

Almost surely, 2^11721291 is an apocalyptic number.

11721291 is a deficient number, since it is larger than the sum of its proper divisors (3907101).

11721291 is an equidigital number, since it uses as much as digits as its factorization.

11721291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3907100.

The product of its digits is 252, while the sum is 24.

The square root of 11721291 is about 3423.6371010959. The cubic root of 11721291 is about 227.1564899964.

The spelling of 11721291 in words is "eleven million, seven hundred twenty-one thousand, two hundred ninety-one".