11431521 has 12 divisors (see below), whose sum is σ = 17381520. Its totient is φ = 7219800.

The previous prime is 11431489. The next prime is 11431549. The reversal of 11431521 is 12513411.

11431521 is a `hidden beast` number, since 1 + 143 + 1 + 521 = 666.

It is not a de Polignac number, because 11431521 - 2⁵ = 11431489 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11431494 and 11431503.

It is not an unprimeable number, because it can be changed into a prime (11431561) 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 11 ways as a sum of consecutive naturals, for example, 33255 + ... + 33596.

It is an arithmetic number, because the mean of its divisors is an integer number (1448460).

Almost surely, 2^11431521 is an apocalyptic number.

It is an amenable number.

11431521 is a deficient number, since it is larger than the sum of its proper divisors (5949999).

11431521 is a wasteful number, since it uses less digits than its factorization.

11431521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66876 (or 66873 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 11431521 is about 3381.0532382676. The cubic root of 11431521 is about 225.2689524552.

Adding to 11431521 its reverse (12513411), we get a palindrome (23944932).

The spelling of 11431521 in words is "eleven million, four hundred thirty-one thousand, five hundred twenty-one".