11239821 has 6 divisors (see below), whose sum is σ = 16235310. Its totient is φ = 7493208.

The previous prime is 11239807. The next prime is 11239841. The reversal of 11239821 is 12893211.

It can be written as a sum of positive squares in only one way, i.e., 6702921 + 4536900 = 2589^2 + 2130^2 .

It is not a de Polignac number, because 11239821 - 2¹¹ = 11237773 is a prime.

It is a super-2 number, since 2×11239821² = 252667152224082, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11239841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 624426 + ... + 624443.

It is an arithmetic number, because the mean of its divisors is an integer number (2705885).

Almost surely, 2^11239821 is an apocalyptic number.

It is an amenable number.

11239821 is a deficient number, since it is larger than the sum of its proper divisors (4995489).

11239821 is a wasteful number, since it uses less digits than its factorization.

11239821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1248875 (or 1248872 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 11239821 is about 3352.5842271299. The cubic root of 11239821 is about 224.0026373520.

The spelling of 11239821 in words is "eleven million, two hundred thirty-nine thousand, eight hundred twenty-one".