11721005 has 8 divisors (see below), whose sum is σ = 14805600. Its totient is φ = 8883216.

The previous prime is 11720981. The next prime is 11721013. The reversal of 11721005 is 50012711.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 11721005 - 2¹⁸ = 11458861 is a prime.

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 7 ways as a sum of consecutive naturals, for example, 61595 + ... + 61784.

It is an arithmetic number, because the mean of its divisors is an integer number (1850700).

Almost surely, 2^11721005 is an apocalyptic number.

It is an amenable number.

11721005 is a deficient number, since it is larger than the sum of its proper divisors (3084595).

11721005 is a wasteful number, since it uses less digits than its factorization.

11721005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123403.

The product of its (nonzero) digits is 70, while the sum is 17.

The square root of 11721005 is about 3423.5953323955. The cubic root of 11721005 is about 227.1546424387.

Adding to 11721005 its reverse (50012711), we get a palindrome (61733716).

The spelling of 11721005 in words is "eleven million, seven hundred twenty-one thousand, five".