11507221 has 6 divisors (see below), whose sum is σ = 12648566. Its totient is φ = 10461000.

The previous prime is 11507213. The next prime is 11507261. The reversal of 11507221 is 12270511.

It can be written as a sum of positive squares in only one way, i.e., 8820900 + 2686321 = 2970^2 + 1639^2 .

It is not a de Polignac number, because 11507221 - 2³ = 11507213 is a prime.

It is a super-2 number, since 2×11507221² = 264832270285682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11507261) 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 5 ways as a sum of consecutive naturals, for example, 47430 + ... + 47671.

Almost surely, 2^11507221 is an apocalyptic number.

11507221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11507221 is a deficient number, since it is larger than the sum of its proper divisors (1141345).

11507221 is an equidigital number, since it uses as much as digits as its factorization.

11507221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95123 (or 95112 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 11507221 is about 3392.2295028491. The cubic root of 11507221 is about 225.7651056208.

Adding to 11507221 its reverse (12270511), we get a palindrome (23777732).

The spelling of 11507221 in words is "eleven million, five hundred seven thousand, two hundred twenty-one".