11003121 has 10 divisors (see below), whose sum is σ = 16436882. Its totient is φ = 7335360.

The previous prime is 11003107. The next prime is 11003137. The reversal of 11003121 is 12130011.

It can be written as a sum of positive squares in only one way, i.e., 10497600 + 505521 = 3240^2 + 711^2 .

It is not a de Polignac number, because 11003121 - 2¹¹ = 11001073 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11003021) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 67840 + ... + 68001.

Almost surely, 2^11003121 is an apocalyptic number.

It is an amenable number.

11003121 is a deficient number, since it is larger than the sum of its proper divisors (5433761).

11003121 is an equidigital number, since it uses as much as digits as its factorization.

11003121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135853 (or 135844 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

The square root of 11003121 is about 3317.0952654393. The cubic root of 11003121 is about 222.4190405282.

Adding to 11003121 its reverse (12130011), we get a palindrome (23133132).

The spelling of 11003121 in words is "eleven million, three thousand, one hundred twenty-one".