11547721 has 2 divisors, whose sum is σ = 11547722. Its totient is φ = 11547720.

The previous prime is 11547719. The next prime is 11547791. The reversal of 11547721 is 12774511.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10890000 + 657721 = 3300^2 + 811^2 .

It is a cyclic number.

It is not a de Polignac number, because 11547721 - 2¹ = 11547719 is a prime.

Together with 11547719, it forms a pair of twin primes.

It is equal to p₇₆₀₂₅₈ and since 11547721 and 760258 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11547721.

It is not a weakly prime, because it can be changed into another prime (11547791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5773860 + 5773861.

It is an arithmetic number, because the mean of its divisors is an integer number (5773861).

Almost surely, 2^11547721 is an apocalyptic number.

It is an amenable number.

11547721 is a deficient number, since it is larger than the sum of its proper divisors (1).

11547721 is an equidigital number, since it uses as much as digits as its factorization.

11547721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1960, while the sum is 28.

The square root of 11547721 is about 3398.1937849393. The cubic root of 11547721 is about 226.0296577885.

The spelling of 11547721 in words is "eleven million, five hundred forty-seven thousand, seven hundred twenty-one".